Earlier quoted context omitted.
This get's into some really complex cost benefit analysis. They directly pay more in taxes with that extra earnings. However, something like smoking has negative externalities so a specific tax on smoking is justifiable. But, education has positive externalities so subsidizing it is justified. Consider, a doctor might make more money but the value of the lives they save is greater than their income. So, it's really a…
Actually, calculations on the social cost of smoking are complicated. We pay more for their healthcare initially, but they die younger so we pay their social security for less time. Depending on how you calculate it, smoking can be seen to be cost neutral, or even to save the country money. http://www.huffingtonpost.com/2009/04/08/how-much-does-smoki...
http://www.babycenter.com/0_how-smoking-during-pregnancy-aff...