Personally, and I usually don't say this, but this has the 'nanny-state' feel to it. Ban smoking in closed public areas , fine. But to extend this ban to open-air patios is going too far, in my opinion. The next step is to ban smoking altogether, and while smoking is undoubtedly a hazard, if you're going to ban smoking for that, the next step is alcohol. Kills just as many people, and its not a substance that you have to have. Sure, you can argue secondhand smoke. Fine. Personally, and I acknowledge medical science may easily prove me wrong, I doubt the truly ill health benefits of walking through a cloud of smoke in an open-air environments a few times a day. I mean realistically, if you use the arguement that sometimes it's unavoidable, or in your way, you're only talking about being exposed for a few minutes at a time. Anything longer, and you have the choice to move somewhere else. But even if we're talking about the ills of secondhand smoke, what about the effects of alcohol on non-drinkers. Drunk driving etc. Personally I think smokers are an easy target because it's annoying, but in terms of actual health costs to non-smokers, we've eliminated the major cause of secondhand smoke which is repeated exposure in poorly ventilated areas. Now we're talking about eliminating smoking in public, open-air spaces. I question that. You can't legislate away everything that annoys you.
Again, my personal, and admittedly uneducated, opinion. I don't disapprove of it exactly, I just think its going too far. I definitely do disapprove of banning smoking in general.