Smoking is a legal activity. If we ban smoking at public places, then what’s next, banning cheeseburgers?
The concern is when someone’s activity, legal or not, is causing harm to someone else. Your sitting next to me and eating a cheeseburger is not going to contribute to my risk for a heart attack; but, your smoking next to me will. The risk from secondhand smoke is real – the risk from secondhand fat isn’t. Under effective policy, smokers can continue to smoke – just not in a manner to harm others.