Prisons are designed, outside the scope of entrapment, to house, clothe, and feed a dense resident population. The resources spent on security could easily be diverted to quality of life improvements.

The organizations that run private prisons off tax subsidies could easily be retooled, in part, to the logistical administration of homeless shelters. They already have on-site detox programs.

You could even retool the current exploitative work programs into trade training.