Helping the homeless get their life back is both cheaper and more humane
sacbee.com
sacbee.com
Coupled with a more general: it costs money to provide healthcare, etc but even if it’s way less than the total cost of not doing so, the latter costs are spread out over more or less everything else so it’s hidden.
This is much like prison and jailing: while there are some people you can’t “correct”, the vast majority you can. Every study has found that providing support and training, etc results in a far lower long term cost it “looks” expensive. When you add in many people wanting prison to be purely punishment, you just end up with people going to jail and often coming out /worse/ than when they went in.
Another property of the “not caring for the mentally ill” is that the mentally ill often subsequently end up in jail - something that costs way more than even keeping them in a mental health hospital if that’s what is needed (the staffing requirements for a mental health hospital are different from those of a prison)
I suspect this doesn't include the cost of land, something of particular concern in the same areas where homelessness is most concentrated.