Never smoked. My dad did, and it just never made sense to me as a kid. The logic that came to my mind was "wait, you pay lots of money to smell that stuff intentionally?". Totally baffling.
For the most part I don't mind if people smoke, provided they do it away from me. What bothers me in a more public sense is that my taxes will eventually go to treating their health care costs (edit: this is probably entirely offset by the taxes levied against cigarettes come to think of it), and that they are denying themselves and/or their families a much higher standard of living.