No, smoking is not natural and neither is prepared food, soda, gardenburgers, beer, wine, or doing anything else that mankind has had a hand in (would that include coasters? or even this forum ) Smoking has been around for a LONG time. And you don't need a very civilized civilization to have it ( ask the british, the indians, etc.) And good luck to you too, seems as though you have a better chance of dying in a car accident than you do of dying of second hand smoke. (and those nasty side effects of such a wreck, could even lead to a vegitative state. I have my living will,....do you?)
All the best
robintodd