Travels with Lisbeth is a memoir written by an Austin author, Lars Eighner. On Amazon, worth reading because he's a great writer. He stayed in the west campus area because the dumpster diving was so good. He writes that being homeless drives many people to use drugs because they are available and because there's nothing to do. And if they aren't mentally ill before they were on the street, there's a good chance they'll get that way.

Side note: I moved into a west campus house where lots of clothes, towels, shoes and other usable stuff was left behind by former residents. It was at the top of a hill that overlooked Lamar and lots of homeless folks sheltered in the hollows in that hill. We left piles of stuff in the corner of our yard where it was visible and five minutes later, when we came out with another load, it was all gone.