Harm reduction and rehab still only treats the symptom, not the cause. The cause is financial instability brought on by insecurity in housing, food access, etc. It's an issue of human dignity in the economic sphere that drives people to such depths, not recreation.

Unfortunately we still have a large portion of the population who believe that one must deserve to live a dignified life, and then apply all sorts of caveats on who is deserving. So we can't reshape the economy to support everyone because the people at the top need to feel like the work they did to get there somehow speaks to their character rather than merely their circumstances. They can't accept that they're not actually that special and so have some pathological need to draw lines between "us" and "them" (e.g. "taxpayer" vs "freeloader").