Some countries are starting to ban smoking - look at New Zealand. Personally I am not against it specifically - if you are going to do some kind of extra harmful drug it might as well at least be one that is not so damn boring like Nicotine.

Obese people is a more complicated issue and I would argue that (at a societal level) it is an indicator of a larger social problem that is then causing the issue downstream just like other issues of addiction. I think we would be better off targeting that issue upstream.

That being said I do really like that in some countries (Japan, from what I hear) your general doctor can prescribe you basic things like "exercise". It must be painfully obvious to so many doctors out there that the best solution to some problems is to get the person actually moving more but instead they have to beat around the bush with after the fact duct tape type medical fixes.