Apparently, there is a whole subculture of people known as “Vandwellers”. (People who live in their vans). I can see the utility in doing this if you were a grad student and you wanted to avoid racking up a bunch of student debt. Definitely. But I’d have a hard time doing the same thing at 40, unless it was in an actual Class B RV with a bed, toilet and shower.
Some people do, though.
Here are a few interesting links: