pray tell what good comes from a bic mac, other than the satisfaction of eating tasty junk food? I'm not trying to promote smoking here, but according to smokers I know, cigarette smoking can have certain therapeutic effects on certain people.
sorry, but eating a bic mac IS inherently unhealthy - did you know the reason they have pickles in the burgers at mcDonalds is because there's so much sugar in the bread and sauces that it would technically have to be classed as a dessert? And, as we saw in that move "Supersize me", eating mcDonalds every day damages your health far more and more quickly than smoking does to the average smoker. I know people who've smoked for years and don't even cough yet. I'm not trying to make out that smoking is healthy, but as with many things, with serious moderation, it doesn't do any more harm to you than other things we do in life, like drinking or eating junk food.
Smoking is bad for you, correct. VERY bad for you. But so are a lot of things and we don't just ban them. In my view, the reasons you give for smoking being absolutely banned are nowhere near strong enough. They merely support bans of smoking in public, which is something I think quite a lot of us can agree on.