I don't want to bemoan this. There's some people who don't have the resources to house a bunch of people but do have authority over a parking lot. I applaud anyone doing what they can for others with what they've got.

Balance compassion for self and others.

When I was in school there were a handful of people (couple dozen in a student body of ~10k) who did it. They'd use the athletics center for shower and the buildings allowed 24hr key access for bathroom. Most of them had jobs in dining services for the free meal per shift. These people weren't looked at as being poor, they were looked at as hard-assed cheapskates who were toughing out a hard lifestyle and consequently saving money in the process and were generally envied for doing something most couldn't stomach. If you can tolerate it it's a great deal if you're a student because you can use student access to facilities to cover a lot of your other needs and it's truly just a place to sleep and the ~20yo body can tolerate the lifestyle. Motorhomes weren't allowed and they were real touchy about box trucks so minivans and conversion vans were mostly what you'd see though there was the occasional station wagon.

And this was not in a mild climate, wikipedia says the mean daily temp in January is 18deg (freedom). That said, I have no doubt that snootier universities didn't allow these sorts of things and would harass the shit out of you with their PD if you tried this there.