At the risk of readers concluding that we’re anti-plastics, which we aren’t, this Mind Over Money post will bring to your attention some important new insights, courtesy of the Journal of Consumer Research, concerning yet another downside of using credit and debit cards. You’ll want to think about it the next time you go shopping (online or off). In a series of lab experiments, Manoj Thomas, Kalpesh Kaushik Desai and Satheeshkuma Seenivasan demonstrated that shoppers who pay with credit or debit cards are more likely to make impulsive junk food purchases than those using cash. In one experiment, for example, participants — who thought they were partaking in a “Food Shopping Study” conducted by a large retail chain — were asked to evaluate a series of 20 items, which unknown to them had been independently evaluated as either a “vice” (e.g., cookies, soda, cheesecake) or a “virtue” (oatmeal, granola bars, whole wheat bread). After viewing each item, participants were asked to decide whether to add it to their shopping cart or continue on to the next item. The result: Participants who’d been told that they could use any of four popular credit cards were more likely to buy vice products.
That is, the cheapening of money that results from credit or debit card use is heightened when we’re mulling bad-for-us choices. And, for the record, this effect is evident in the real world, too. As part of their study, the three researchers analyzed the shopping behavior of 1,000 households over the course of six months. Turns out, the carts of actual shoppers who use plastic are more likely to contain a larger portion of “vice” items than the baskets of those who use cash. To put this into proper perspective, it’s been known for quite a while that credit and debit cards make for poor shoppers, because using them leads people to buy more things and pay more for them, thanks to mental accounting. Now we also know that plastic also increases the likelihood that people will spend money on things that are unhealthy or (presumably) otherwise bad for them.
Like we said: We’re not anti-plastic. Credit and debit cards are tremendously convenient. Credit cards, moreover, can serve as excellent sources of emergency funds. And for many individuals and families they serve other useful and responsible purposes as well. But if you’re trying to shrink your spending — or your waistline — your best move might be to curtail your use of plastic and other devices (like online payment systems) that provide a dangerous mental distance from the reality of what you’re actually doing to yourself and your finances.