Those finicky self-scanning checkout machines have more issues than just refusing to scan your bag of dog food. They also might actively encourage shoplifting, according to a new University of Leicester criminology report [PDF], which we spotted on Vocativ

The report analyzed phone-based self-checkout systems over a period of just over a year at four UK retailers, two in the U.S., one in Belgium, and one in the Netherlands. Out of about 12 million shopping trips, one million were audited by employees to see if people were paying for what they carried out of the store. They found that while self-checkout payment systems might be beneficial for getting people out the door without the need for human cashiers, they also make it so easy for people to steal—whether on purpose or by accident—that they’re cutting into retailers' bottom lines. 

One theory on why the tech leads to theft? Frustration. Self-checkout machines can be cumbersome, requiring people to call over staff for help or to check IDs on purchases like alcohol. Other times they just seem to refuse to scan the item you’re trying to pay for. That kind of friction can give people an extra nudge to just put the item in their bag. 

The criminologists also suggest that “retailers might actually encourage shoppers who fully intend to scan and pay for products to engage in criminal activity” by using these kind of self-checkout systems. It’s just too easy, and people feel like no one is watching. “As one respondent said: ‘What you might see is people who traditionally don’t intend to steal but realize … when I buy 20, I can get five for free… maybe I’ll continue to do that.’” You can simply put an item in your bag on the floor instead of on the scale, “accidentally” forget to scan a large purchase on the bottom of your cart, or label a by-weight item like fruit as a cheaper item.

The study found that stores that used self-checkout options experienced much larger losses than stores without them—122 percent more. The self-checkout shopping trips equated to almost a four percent loss for the store, compared to the average store-loss rate of 1.8 percent the researchers calculated based on various security and theft-related datasets. As they note, in Europe at least, grocers operate with a profit margin of about three percent, so losing four percent of sales is a pretty big deal. You might be seeing a whole lot more store employees hovering over your self-checkout lane in the near future. 

[h/t Vocativ]

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