Human nature can't be trusted, yet the people who make the laws are humans and often very flawed humans. ... and I really don't trust them. If you don't think all the toffs are snorting lines of coke at parties, then I think you are being a little naive.
It's very complicated, those folk you see on skid row... It's never clear if they are crack addicts because of their situation or they are in that situation because they are crack addicts. I think it's often the former, so the drug addiction is a symptom of their situation, rather than the cause.
Honestly I think the law makers just think it's too bigger problem to even start trying to deal with. I also think there's a pretty good argument to say that some of the main reasons people end up that way and in those situation is the direct consequence of the actions of those people with the power to make laws.
I'm not sure, it's a massive subject because nothing exists in a vacuum. The 'drug problem' is so intertwined with everything else.