In the U.S., there isn't much of a waiting list for most things as far as medical treatment. There are a million things that are bad for you. Should we have extra taxes on people who drive more, eat more fast food, scuba dive, parasail, exercise less, etc.? In a system in which people pay for their own medical care and insurance, smoking is your own business (and perhaps that of your insurance company). But there's no shortage of medical care that isn't created by government intervention. I mean, there's a definite shortage of free medical care to be sure.

If I'm driving dangerously, I'm endangering other people. That's different than not wearing a seatbelt in which case you are really only endangering yourself.