If you ask someone directly whether they consider themselves a thief, the overwhelming majority will say no. Most people imagine theft as a deliberate, premeditated act—something committed by “other people,” not ordinary shoppers who just want to get home with their groceries. Yet self-checkout machines have revealed something uncomfortable: when opportunity collides with anonymity, many otherwise honest individuals behave in ways they never thought they would.

Self-checkout lanes were introduced with the promise of convenience. They were supposed to streamline the shopping process, reduce labor costs, and give customers more control over their experience. Instead, they opened the door to a new era of casual theft—so subtle, so effortless, and so common that it has become part of the cultural landscape. The “banana trick,” once an obscure joke among mischievous shoppers, now symbolizes a much larger issue: the collision of human behavior, technology, morality, and temptation.

This is the story of how a simple machine changed how people steal, why they do it, how retailers are fighting back, and what this means for the future of shopping.

The Banana Trick: Theft Hidden in Plain Sight

At the center of the conversation sits a notorious move: the banana trick.

It works like this:
A shopper takes an expensive item—say, a ribeye steak or a bottle of premium olive oil. Instead of scanning the barcode, they punch in the four-digit code for bananas or another cheap produce item. The machine accepts the entry without suspicion. The shopper pays pennies on the dollar and walks out smiling, convinced they have outsmarted the system.

For years, this trick has been the unofficial mascot of self-checkout theft. It reveals exactly why these machines are vulnerable: they rely on honesty. They are built on the assumption that people, when left alone, will tell the truth about what they’re buying.

But as studies have shown, that assumption crumbles quickly when temptation is placed in front of the average shopper.

Voucher Codes Pro surveyed 2,600+ consumers. Nearly one in five admitted to stealing through self-checkout at least once. More than half said they did so because they believed they wouldn’t be caught. These weren’t career criminals. They were everyday people—students, parents, office workers, retirees—who simply found a loophole and couldn’t resist exploiting it.

The banana trick is just one method. Many others have emerged organically, each one representing a slightly different approach to dishonesty.

The Pass-Around: Theft by Pure Simplicity

This tactic is almost insulting in its ease. A shopper lifts an item—usually something small, lightweight, and expensive—passes it around the scanner, and drops it in the bag without scanning it. No deception required. No technological skill. Just a quick motion that, if done confidently enough, blends into normal shopping behavior.

For many, this is the gateway technique. It feels small. It feels harmless. It feels like the machine’s fault for not noticing.

And it works—until it doesn’t.

The Switcheroo: Theft by Reassignment

More sophisticated thieves use the “switcheroo.” They remove a barcode from a cheap product, stick it onto a more expensive one, and scan the swapped label. To the machine, everything looks normal. To the shopper, the savings are enormous.

This tactic is surprisingly common because it requires just two things:
a little preparation and a little nerve.

The risk of being caught still exists, but the moral burden is lighter for some because the act of scanning “something” tricks the brain into thinking they paid—even if they didn’t pay the correct amount.

The Fallout: How Much Theft Actually Costs Retailers

The numbers are staggering.

Criminologists at the University of Leicester studied over a million self-checkout transactions in a single year. Out of $21 million in sales, $850,000 worth of merchandise walked out unpaid.

Nearly one million dollars lost because the machines trusted humans more than humans trusted themselves.

Self-checkouts were designed to cut labor costs, but the losses from theft often outweigh those savings. Retailers now find themselves locked in a technological arms race: making machines convenient enough for honest shoppers while sophisticated enough to deter dishonest ones.

Why People Steal When They Never Planned To

Researchers in Leicester discovered something fascinating: many people who steal at self-checkout never intended to steal when they entered the store. The temptation arises only after they reach the machine.

The environment changes their behavior.

Self-checkout creates:

Anonymity

A sense of reduced accountability

A loophole too tempting to ignore

As one researcher put it, self-checkout offers people who would never shoplift by hand “a crime of opportunity”—a moment where morality is softened by convenience and the illusion of invisibility.

Another factor: lenient consequences. In Dallas, police stopped responding to thefts under $50, later raising that threshold to $100. When people see reduced enforcement, some interpret it as permission.

The Psychology Behind the Theft: More Than Just Opportunity

Barbara Staib of the National Association for Shoplifting Prevention believes self-checkout creates a psychological buffer. Because there is no human cashier, shoppers can convince themselves no one is being harmed.

She calls it “the false impression of anonymity.”

For many, the machine becomes the victim—not the store, not the employees. And because a machine cannot express emotion or disappointment, guilt evaporates.

Criminologist Shadd Maruna expands on this idea. People justify theft by arguing that corporations can afford the loss. They convince themselves they are correcting an injustice—believing stores are greedy, prices are unfair, and automation has cost workers their jobs.

In other words, some shoppers frame theft as an act of balancing the scales.

Finally, psychologist Frank Farley identifies a personality trait present in many self-checkout thieves: thrill-seeking. For these individuals, shoplifting turns ordinary shopping into a game. The risk is intoxicating. The reward is exciting. The moral consequences feel distant.

To them, the self-checkout machine is not a barrier—it is a challenge.

Why Retailers Keep Using Self-Checkout Despite the Losses

With theft rising, you might wonder why stores continue to rely on these machines.

There are three main reasons:

1. Labor Costs

Self-checkout reduces staffing needs. Even with theft, many stores still come out ahead compared to full staffing.

2. Consumer Preference

Some customers prefer self-checkout for privacy, speed, and autonomy. Target reports that roughly a third of shoppers prefer machines over human cashiers.

3. Technological Evolution

The machines are getting smarter, faster, and harder to fool. Retailers believe that once the technology matures, the cost-benefit balance will tip strongly in their favor.

But until then, theft remains an ongoing battle.

The Technological Counterattack: Cameras, AI, and Pattern Recognition

Self-checkout theft became so rampant that stores had to redesign their defense systems. Many weight-sensitive detection platforms were disabled after customers complained about constant false alerts, which made the machines malfunction and slowed down the process.

Removing the weight sensors made theft easier—but retailers had a plan.

NCR’s Video Monitoring

NCR Corp, the maker of many Walmart self-checkout systems, introduced real-time video monitoring. When the system detects something suspicious—like a missed scan—it sends a clip to remote staff who review the footage and decide whether action is needed.

Everseen’s AI System

After removing weight sensors, Walmart partnered with Everseen Ltd. Their AI-driven camera system tracks every movement: items, hands, motions, and scanning patterns. If a customer performs a pass-around or mis-scan, the system pauses the transaction immediately and alerts an employee.

This transforms theft from a low-risk act into a high-risk gamble.

Facial Recognition and Behavior Tracking

Some stores have begun experimenting with:

facial recognition to flag repeat offenders

shopping pattern analysis to detect suspicious behavior

predictive algorithms to anticipate theft attempts

While controversial, these systems are becoming more common as retailers attempt to reclaim billions lost each year.

The Ethical Debate: Is the Machine Making Us Worse, or Revealing Who We Are?

Self-checkout raises uncomfortable moral questions.

Would the same shoppers steal from a human cashier?
Would they slip items into their bags if someone were watching?
Would they commit the same crime if a person handed them change and smiled at them?

In many cases, the answer is no.

The machine doesn’t judge. It doesn’t look disappointed. It doesn’t form a human connection that might restrain impulse.

Self-checkout reveals that morality is often social, not internal. People behave better when they feel seen. When that social accountability vanishes, some discover that their moral compass is more flexible than they believed.

Does this make technology the problem? Or does it simply expose what was always there?

The Future of Self-Checkout: Evolution or Extinction?

As theft becomes more sophisticated, so do the machines. In the next decade, we may see:

biometric scanning

carts that auto-detect what you take

AI systems that track item-to-hand contact

stores that eliminate checkout entirely (Amazon-style grab-and-go)

harsher penalties for self-checkout fraud

The banana trick may soon become impossible—not because people changed, but because technology caught up.

Retailers are not giving up on automation. They are refining it, reinforcing it, and preparing for a future where checkout theft becomes nearly impossible.

Conclusion: The Machine Isn’t the Thief—People Are

Self-checkout didn’t create theft. It revealed the conditions under which ordinary people become thieves:

anonymity

opportunity

low risk

moral justification

technological loopholes

The banana trick is a symbol, not the root of the problem. It represents a shift in how people interact with businesses, with machines, and with their own conscience.

As technology tightens its grip and surveillance evolves, the freedom that made self-checkout theft so appealing will shrink. But the deeper lesson remains:

When people believe no one is watching, many behave differently.
When machines replace human eyes, morality shifts.
And when opportunity feels harmless, temptation becomes powerful.

The future of retail isn’t just about better machines—it’s about understanding human behavior.