Ok, sure, yes, smokers do essentially bring the harm upon themselves but, think of all the other ways people can do that, drinking, illegal street racing, idiots that attempt suicide, drug addicts.
It's all a matter of opinion in the end rue, but, think about it, sure smoking can cause some serious damage but compare it to that amount of damage drugs can do to the body and not just physically but mentally, and people who really mess themselves up with meth and coke and then get picked up by the state and put into rehab clinics where tax money is wasted on getting them better. And everyone just yells about how bad smokers are, in the end they can be considered addicts as well, cause Nicotine is just as bad as any other drug in many ways, quitting isn't easy.
Some people are just not that badly affected by smoking, my uncle has smoked all his life, even before he was legally allowed, and he still runs 3 miles in a little under 11 minutes. Some people are just naturally more at risk for it and some people more naturally resistant. Now, I don't agree with treating those who won't stop when their getting treatment cause then their just making a problem worst, sure it's irritating that many wait till the problem is at it's worst but I don't see why we should stop offering immediate healthcare to those who mess up themselves. I don't think it's fair to give them any more healthcare than anyone else but I don't see it as fair that they should be denied treatment until a later date, first come first serve with some minor excepions for major issues, it may suck sometimes but its about as fair as you can get.