If people want to smoke, let them smoke. Is it bad for them? Yeah. Does it have a negative cost against society? Yeah. But its a slight cost that I'm willing to bear to uphold personal liberty and freedom of choice.
Overall, smoking rates are pretty low, and we're probably on the other side of the overall costs smoking writ-large will have on society. So its fine. If people still want to smoke, warn them of the negatives, then let them smoke.
The reason I'm so against more regulation is that the current trend in the war against ecigs is to ban pretty much any good tasting flavors (all but menthol), and I don't like that what entails for our future. I don't even vape, but the idea that the majority will go around banning what they don't like "for the good of the children" is something I refuse to support.
It's not going to stop if it gets started.