another thing that people don't realize (and i had no idea, either, until i looked into it) is that the leading cause of homelessness amongst youth is not addiction or mental illness but....
homosexuality.
that's the sad truth: a very strong plurality of the kids you see on the street were kicked out of their homes for the crime of being queer. it follows that addressing attitudes around this very specific issue should cut homelessness rates by nearly 50%, and also that the shelters should be organizing themselves around the very specific issue of dealing with queer youths.
but, you have to take the time to figure that out before you realize it.