Tell that to Caribou (CBOU) Coffee CEO Mike Tattersfield, who had his secretary special order a set of satin superhero capes for his company’s annual recognition luncheon last month. There are two with superhero logos, four with lightening bolts, and then Tattersfield’s own (which was not ordered but came free of charge as a thank-you), made from white polyester satin with the Caribou logo in felt sewn on the back — intended to mimic the look of an actual cup of Caribou coffee.

The capes were used as a kind of icebreaker at the luncheon last year, and they still get some use around the office, says Tattersfield. While CEOs walking around the office in costume is not part of everyday corporate life, per se, Caribou has company. The coffee establishment’s capes were among thousands constructed for corporate use by five-year old start-up Sew Plain Jane, which, until recently, operated out of 35-year-old founder Dawn Rivera’s spare bedroom in Holly Springs, Ga.

Rivera went into the cape business so she could spend more time at home with her three kids, who are 2, 6, and 8, respectively. Before starting Sew Plain Jane, she had some misadventures with a natural soap and skin care company she founded that managed to move a lot of soap, but didn’t make any money. With capes, she says, there’s a higher margin and a startlingly large market. “It was shocking to me that people were so crazy for superhero capes,” Rivera says.

After a slow start making capes mostly for birthday parties for a few months, Rivera began to notice that her wares were making their way to the office. Lutheran General Hospital in Illinois gave them to staffers who pulled all-nighters during a blizzard. Other companies handed them out to standout employees or at retirement parties.

Eventually, Rivera found an even less likely market — the company leadership seminar. Health company Herbalife brought out custom-made company capes at a corporate function as a way to lighten the mood, Rivera says. Penn Foster Career School bought a few to use at a training session. Intel (INTC) has bought some, as has Dunkin’ Donuts (DNKN), Krispy Kreme (KKD) and Susquehanna Bank (SUSQ). But it was Caribou that took to it with the most aplomb, bringing the capes out at that first luncheon, and then at subsequent earnings briefings and leadership powwows.

Hearing about the executive luncheon, Rivera is still in awe: “It was just so cool. Honestly, at first it seemed silly to me, but they did — they wore them while they were in there.”

In photos of the luncheon, some of the caped executives don’t exactly appear at ease. But Tattersfield, known for his unconventional work style (his desk is a functioning foosball table), says the company’s culture centers on “disruptive behavior” that draws attention. At a company that is looking to stage a turnaround, as Caribou is, there’s often a premium on upending the norm. Caribou, whose national reach is second only to Starbucks’ (SBUX), saw its best year ever in 2010.

Rivera does her part to make disruptive behavior affordable, with capes starting at $5 a pop. On occasion, Tattersfield says, “when I present to the team, I do wear a cape.” And they’re multi-purpose. Says the CEO: “The kids love ’em.”