those potheads will create inefficiency in our society. Crime too. Their lack of productivity, on a macro level, will mean less people for the mundane jobs. harder to get a burger. economy takes the hit as a result. crime goes up, as folks gotta eat
IMO libertarianism cannot work in a capitalist system - there are just too many stupid people who would make the streets unsafe for those of us who give a shit.
Libertarianism and capitalism grew out of classical liberal ideals. I think both libertarians and capitalists know who Adam Smith was...
Why were people like Milton Friedman libertarians then?

I'm sure he was a capitalist as well.

Alcohol is an example of a legal, but highly regulated drug that causes huge problems. I don't think legalized pot would cause a huge amount of driving related deaths or spike the crime rate. Pot does not make people violent by causing them to lose their inhibitions. Your arguement of marijuana making our society inefficient falls flat on its back.
If you were making an arguement against cocaine, then I'd agree with you.
Libetarianism does not mean anarchy and unregulated everyhting.. Right to bear firearms, but restricted licenses and background checks. Legalized cannabis, but not cocaine or heroin. And no one is gonna bulldoze the IRS.. Just reduced taxes.. Besides, we could adopt taxing gasoline like they do in europe and pigovian taxes on negatives, such as pollution. Catch my drift?