The government takes into account the factors which you, as a selfish human being, do not. - When you blow smoke all over someone, they probably would rather you weren't. If that same someone came up to you and coughed in your face, you probably wouldn't be very happy either. - When you get lung cancer and need an expensive operation, it costs all the non-smokers money (assuming you live in a country with a national health service). In America, they'd do the same thing, but instead they'd have a little question on your health insurance which says "smoker Y/N", and if you answered "Y", then they'd up your premium. Therefore, the government imposes restrictions and taxes which take into account the harm you do, but don't care about.