What’s the benefit of living in an RV vs. putting in a mobile/pre-fab home?

I get it if you had the RV first and the land came second but then why buy the land if the laws restrict living in an RV on it?

I don’t really care if people want to do it, I just can’t come up with why.

I do think laws around minimum square footage, requiring connection to utilities etc. are dumb in general.