The reasons you're bringing up are strawmen at best. The people who are homeless or on the brink of homelessness are not complaining about artisanal food stuffs.
In Oakland, a family of 4 has been living in a single family home for 15 years. This year, after new owners purchased the property, the rent went up 100% in one year. Needless to say, they are facing a housing crisis where they will be homeless.
If you want to understand the severity of the situation, I suggest just literally googling "homelessness housing crisis bay area" and read all the both qualitative and quantitive reporting done on the issue.
Here's a brief stat overview to refute your claim that it's a "mental issue" primarily: http://www.socialsolutions.com/blog/2016-homelessness-statis...