There are a lot of reasons that businesses close their doors and I don't believe that you can specifically attribute any of them to a ban on smoking. Sometimes businesses close because they are badly managed. Others because trends change and something new opened down the street that sucked their customers away. The fact remains that smokers still eat, whether they can smoke or not.
Lots of businesses closed as the result of the recent downturn in the economy. Too many people out of work, not enough income. Doesn't mean that a ban on smoking was the cause.
I know I won't change your mind, you already have convinced yourself that the smoking ban is the cause of it all. There is way too much evidence to prove that the smoking ban has had no harmful effect on business operations. Smokers can still smoke, they just can't do it inside a restaurant, anymore. In the long run, they are too small a minority to have asignificant effect on most businesses.
Go ask a hay grower in southern Delaware. He sells his product to the horseman that races at Dover Downs, where purses plunged after the smoking ban at the casinos that funded horse-race purses.
Go ask the John Deere guy who hasn't sold him a baler since then. Ask the guy who runs the diner where the John Deere guy used eat. Ask the restaurant-supply guy who hasn't sold a stove to the diner since.
Etc. ... consider the obvious, logical repercussions of your smoking bans. It doesn't just shut down bars, although there is a long list here in New York City.
I see. 25-30 % of the population is 'too small a minority' to have any effect. That's a joke in itself, but I'll pass on that one for now. What you seem to not understand is, many restaurants and virtually all bars have their business comprised of 75-90% smokers. You continue to believe the horseshit that's spewed forth by the rabid smoker-hating Nazi scum, I'll choose to believe my own eyes, thanks. I knew several of those former business owners personally. Your business does NOT become virtually non-existent overnight after being around 20-40 years without outside interference. And they all knew what it was in this case. The voters had to wait a year for it to be on the ballot (thanks to a screw job by the city the first time it was tried), and some of them just couldn't hold on. Enjoy your envisioned utopia where everyone is as perfect as you.