The food service industry is just chock full of cigarette smokers. According to a recent CDC study, as much as 30% of Americans working in food service over the age of 18 smoke. That's kind of a lot, considering just 19.6% of working adults are smokers. Of course, as anyone who has worked in the industry can attest, this isn't really surprising news.
A spokesperson for the CDC tells the AP, "there may be other characteristics that are clustering" such as the fact that employees in the food service industry and other high-smoking fields tend to be "younger, have fewer years of education and make less money." So the logic is, what the hell, spend what little money you have on cigarettes?