There is a lot of evidence that it's very effective and cost-efficient just in practical terms, but that is not why I support those policies. I support them because everyone deserves a home. Choosing not to provide one to someone who needs it when we have the ability is vicious and immoral.

What they do after that isn't really relevant to be honest. I'm not trying to polish people into perfect rule following members of society and anyway homeowners get addictions and commit crimes all the time as it is. We don't generally leap to questioning their right to have a place to live though.

If giving homeless people houses solved no other problems it would still be correct and morally necessary.