Bradway said he eats lunch at his desk and keeps his breaks brief, chain-smoking two cigarettes during each of his three daily smoke breaks. "One hits the pavement, another gets lit up," he said.
Hotchkiss and Pitts found that heavy smokers aren't less productive than other workers, but even if they get their work done on time, their earnings still suffer.
The two researchers attribute about 60 percent of the wage gap between smokers and nonsmokers to demographic differences—collectively, smokers tend to be less-educated than nonsmokers, for instance—but the rest were ascribed to what they called, "unmeasured factors."
"The wage disadvantage to smoking has been well documented … [but] hard to believe that the direct unpleasantness of smoking is the main factor," Frank Stafford, an economics professor at the University of Michigan's Population Studies Center, said via email.
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In considering what those other factors could be, Hotchkiss and Pitts mentioned an employer's tolerance for smoking in the workplace. Beyond that, they and other experts theorize that there could be personality traits that differentiate current smokers, former smokers and nonsmokers.
"We suggest that it is something about the persistent smoker's lack of self-control and the inability to quit," Stafford said.
Conversely, smokers display other qualities that can be beneficial in business, said Kim Ruyle, president of Inventive Talent Consulting.
"There's a social aspect to leadership that's important, and there's a social aspect to smoking as well," he said.
And smoking is a risky behavior, which can pay off in certain professions. "Many effective leaders are highly curious, they experiment, they're willing to take more risks than some people will," Ruyle said.
When a smoker quits, they keep those behaviors and add a strong dose of self-discipline—another trait that can help out someone's career.
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"That discipline is useful in the workplace as far as focus on projects and tasks, expectations of similar discipline from subordinates, or simply the discipline for good attendance," George Boué, expert with the Society for Human Resource Management and vice president of human resources at commercial real estate firm Stiles, said via email.
"It takes a whole lot of perseverance to stop an addictive behavior, and perhaps that transfers over into labor market behavior as well," Pitts speculated.
Emily Busscher, a quality control technician at a manufacturing company, said she doesn't think being a smoker since the age of 15 has held her back. "Everybody I work with smokes," she said.
But the 28-year-old Michigan resident acknowledged that quitting might make her bosses think, "She's willing to do stuff, so she can make it places."
Busscher said she has quit smoking for short stretches before. If she kicked the habit for good, "They'd figure I was a stronger-willed person," she said. "I'd be more apt to be like a supervisor or somebody higher than where I'm at."