What we should do for people who are addicted to drugs is unclear. What we should not do to people who are addicted to drugs is clear and that is to put them in prison.
Of course when talking about a society dealing with drugs in a liberal fashion one quickly ends up imagining utopias where people don't have reasons to escape their sad reality. Thinking about better worlds is not a bad thing at all - it's just painful realizing how faaaaar away we are from it.