This study indicates that legislation that mandates smoke-free restaurants attracts more business (and money) than it drives away.
Corsun, D. L., Young C. A., & Enz, C. A. (1996). Should NYC’s restaurateurs lighten up? Effects of the city’s smoke-free-air act [Electronic version]. Cornell Hotel and Restaurant Administration Quarterly, 37(2), 25-33. Retrieved [insert date], from Cornell University, School of Hospitality Administration site: http://scholarship.sha.cornell.edu/articles/480/