Anyone who thinks funding rehab centers and getting homeless drug addicts into free apartment units are people who have never been around homeless drug addicts. There may be some wonderful examples of this working but 99.8% of the people you will encounter on your commute are not about to participate in rehab, and if you ask them they will give you a history of apartments and homes they've been asked to leave due to…
It’s simply an optimization problem. Prison is horrendously expensive, and people on the street have real externalities for everyone in the area.