There are some small number of people who have hit upon desperate times that you’ll occasionally find living on the streets, but by far and away, they’re mentally ill, have major substance abuse problems and often both, and cannot maintain shelter for themselves, they’re that dysfunctional. Some seem to actually prefer it. Homeless shelters fill up when the weather is bad. When it’s not, they don’t.
I agree with everything you wrote except that they prefer to be homeless. They don’t want to be homeless. Most would prefer a home, they just can’t manage it. A lot avoid the shelters because they can be dangerous and/or the individuals can’t deal with the rules or are mentally ill enough that is too difficult to handle.
Seem to always have money for cigs and booze. Or they get them somehow.
Blame Jerry Rivera for that. He's the one who did a tv hit piece on the mentally insane an the facilities back in the 80's, I believe.