One of the things that shocked me the most when I visited another state a few years back was that people were smoking in the grocery stores while shopping!
Here, people cannot smoke in stores, malls, restaurants, bars, offices and so on. I believe there is also a law about smoking within a certain distance of the entry of a public building.
I am really unsure as to the longterm effects of secondhand smoke but the smell itself can be unpleasant and cause teary eyes so it's definitely an immediate irritant.
I think it's a good thing to ban smoking from major public places but I think people should still be able to smoke outdoors. It would be nice if they didn't just drop their butts on the ground tho because those things just never seem to deteriorate.