This is an interesting question, and there are at least 2 schools of thought on the answer.
If it is posed to the antis, they will tell you all the bars and restaurants will survive because all the non-smokers who have been staying away because of smoke will come flocking in and there will be no problem.
If it is posed to the bar and restaurant owners, they will tell you the antis do not come flocking in, and the smokers stay away along with all the non-smoking friends and family of the smokers. additionally they will tell you, smokers tend to stay longer, therefore spending more money, and tipping better.
It always comes right down to this: if the antis wre correct there would be a proliferation of smoke-free bars and restaurants everywhere and thus no need for these intrusive bans. But the antis are wrong, and they know it, but it order to cover up their insidious lies, they push for the all out bans under the guise of "levelling the playing field."
That phrase has become as nearly sickening to me as "it's for the children." It's got nothing to do with the children, because if they really cared about the children they wouldn't be seeking laws that have proven to put small businesses out of business and forcing those owners and employees to find another way to support their children.
Smoking bans are not about health, nor aboout children; they are about power and control. The antis want the power to control others. and the sooner people wake up to that, the better off everyone, smoker and non-smoker alike, will be.
sorry for my rant.