OK, cool. But let's ask ourselves a really important question: can these people really not "will" themselves to stop, or is the fact of the matter that they simply don't want to stop? For most people engaging in the behavior you describe, I submit that their values differ from those of society. For many, they would rather get high than keep a steady job, or would rather gamble than pay their bills. If you ask some of them this question (I have), they will come right out and admit it -- if they are comfortable that you aren't trying to change them.

While I disagree with these choices, because I believe that "Self-Ownership" is philosophically axiomatic, I necessarily believe that it is a person's right to make those choices in their life. Note, however, I do not believe these choices should be acceptable excuses for other behaviors that harm others, such as theft, child abuse, or whatever. It's fine with me if someone wants to spend their life stoned, but it's not OK if they endanger their children as a result. Since endangering children is already a crime, we do not need to legislate further.