[AntEater]

Problem is, Libertarianism is an ideology, just like communism.
Both except people to behave according to morals.
In Communism, people have to put the collective good first, in Libertarianism, people have to be "perfect" sensing opportunities and using them.
Which is a bit far from the reality.
Especially in time when most of the really heavy companies of the western world basically make their money by conning people into making decisions which are NOT in their objective interest (the media, the consumer industry), how can you assume that everyone chooses rationally?
It is not rational for a worker to buy a TV set or a SUV on a loan, yet the economy demands it. Other people making rational choices work day and night to make that guy buy more than he could afford.
For those people, objective right choice would be to buy a smaller TV or a more economic car, thus having more money for medial emergencies, retirement, education or whatever.
Yet if they all did, the whole western economy would collapse...

Re Druggies and so on, some people always fall through, no matter what system or ideology you prefer. Then it becomes a matter of humanity, not of economy.