Look how much fun he’s having. Photo: H. Armstrong Roberts/ClassicStock/Getty Images

Trader Joe’s: home to good snacks and cheap wine and, apparently, mandatory cheerfulness. Late last week, an unfair-labor practices charge was filed with a National Labor Relations Board regional office on behalf of Thomas Nagle, a former employee of a Trader Joe’s located on the Upper West Side. According to the New York Times, Nagle was let go in September after being “repeatedly reprimanded” by management; among his fireable offenses were an “overly negative attitude,” paired with an obviously fake smile.

That he was fired may be a problem for the grocery-store chain, the Times reports, if it turns out that the company’s insistence on maintaining a sunny disposition effectively prohibited him and his colleagues from discussing their dissatisfaction with their workplace. Federal labor law protects employees’ right to “complain about working conditions to the public, including customers.” (Trader Joe’s issued a statement to the Times denying any wrongdoing.)

And yet no matter the decision, there are other reasons that forcing a positive attitude is a bad business practice. Research in organizational psychology calls this sort of thing, which often comes with the territory in the service sector, “surface acting” — for example, slapping on a smile and pretending it’s fine, perfectly fine, that a customer just knocked over the display of Charles Shaw wine. Faking it, in other words. As you might imagine, this gets draining by the end of an eight-hour (or even longer) shift.

In 2003, for example, Alicia A. Grandey of Pennsylvania State University published a summary of surveys filled out by 131 administrative assistants, one of whom confided to her, “It’s frustrating at times to always be courteous and helpful to those who may not act as such in return. We need to keep smiling when we really don’t feel that way.” They were asked to rate, on a scale of one to five, how often they felt like they did the following while at work:

• ”Just pretend to have the emotions I need to display for my job.”

• ”Put on an act in order to deal with customers in an appropriate way.”

In the end, Grandey found a clear link between behaviors like these and “emotional exhaustion,” one of the core components of job burnout. Other research backs up this finding: Faking a cheery attitude is exhausting, and it often results in burned-out employees. As Annie Murphy Paul, a writer and author who often covers social science, noted in a 2014 post on her site, a non–Trader Joe’s example of employer-mandated chipper behavior can be seen at Walgreens-affiliated stores. At my local Duane Reade, for example, as cashiers hand you the receipt they tell you, “Be well.” The first time this happened, I found it touching, believing it to be a genuine kind wish from the stranger at the cash register.

It was not. As Jessica Levco, who edits the website Health Care Communication News, reported, this is company policy. “’Our branded salutations further align our team members to our purpose of helping people get, stay and live well,” a Walgreens spokesperson said in a statement given to Levco. “In general, we’ve found that customer satisfaction increases through such positive interactions, which help make their shopping experience a bit more memorable.”

That may be true, that customer satisfaction increases with changes like these; then again, maybe not. A 2008 study surveyed people who took a fitness class; unbeknownst to them, their instructor had either been told to fake their emotions and act enthusiastically about the class, or to just act naturally. People didn’t fall for the act; they could tell when the instructor’s heart wasn’t really in it, and when they did, they didn’t have as much fun in the class. Having fun is not so fun when the fun becomes mandatory.

Instead, Paul suggests employers consider the following:

Train workers well, so that they satisfy their customers with good service. Offer them congenial working conditions, so that they’re glad to be at work. Allow them more personal control over how they do their jobs (research shows this can buffer the stress imposed by surface acting). And provide them with opportunities to develop genuinely warm relationships with managers, coworkers, and customers — so that employees have something real to smile about, and so that when they tell someone to “be well,” they mean it.

As she pointed out in her post, well-meaning mandates like this one can backfire. Having to behave in opposition to our inner states is known, in the psychological literature, as emotional dissonance, and it is exhausting, physically and mentally speaking. “We all want to feel that we’re the same person on the outside as we are on the inside,” Paul wrote, “and when we can’t achieve that congruence, we feel alienated and depersonalized.”