I agree with most of your post except the part about the occasional cigarette. There was a recent study suggesting that the occasional smoker could suffer more health problems than someone who smokes regularly. I wish I could remember the details. But even if that's some kind of fluke or minor detail, the fact remains that for many people tobacco is terribly addictive, and anyone who has ever smoked knows that you have that one cigarette it's very easy to be smoking a whole pack by the weekend. People who can smoke just one and leave it alone for a month or a year are rare birds.