There should be concern about those who are forced to work in smoky environments. What's going to happen if a single mother is forced to work as a waiter in a smoky restaurant just to have food and not slump into a dependence of welfare/charity? I don't think it's worth forcing people to spend hours every day in fuming environments. Customers have the right to harm themselves, but workers should not be subject to such dangerous working conditions. Otherwise, there's apparently a "right" not to wear a helmet in a construction site, a "right" not to wear safety goggles in chemical labs, and a "right" to work on dangerous equipment without training. Perhaps smoking in restaurants should be allowed, but only if, say, waiters wear gas masks. How will that look?
