Mainstream US society tries to make something radical and perverse about having "no fixed address."Society (and some of its laws) don't mind if you constantly wander, as long as you have some building somewhere you claim as "home." Take away that building and, presto, you're a bum, even though your day-to-day life is identical to the constant wanderers who never set foot in their "home."
Take your "home" with you wherever you go? That's radical and perverse. Not wanting to be attached to a building? That's totally beyond most of society's understanding. Therefore it's highly suspicious, and therefore probably criminal.
A threat to society?
By society's standards, I'm homeless. I live in a van, fer crying out loud. That's what losers do. That's what sketchy people do. That's what drug addicts and child molesters do. Society doesn't care that I do it by choice, that I'm retired, that I have money, that I behave myself, that I just want to travel cheaply. No building = homeless.
What about those people in big ass RVs? Funny how no one thinks of them as homeless. Everyone's fine with John and Mary spending their golden years drifting around the continent. Society doesn't think to ask if they have a building somewhere. Because, money.
"Homeless" is actually about class. Exude enough upper-middle-class respectability and people give you a pass. They might even envy your freedom. But do the exact same thing as John and Mary in a low-budget way? The pariah alarms go off. Danger! Danger! Poor people!
Let's do an experiment. Take John and Mary out of their shiny new RV and put them in one that has seen better days. What does society think of them now? Put them in an even more tired RV, and so on, down, down, down the economic scale. When do they cross the line, when does society become uncomfortable with them and start thinking of them as undesirable transients, as poor, as homeless?
Can a lone guy in a self-converted cargo van ever rise above that line? I don't think so. People who figure out I'm not a tradesman, that I'm actually living in the van, will probably put me in the homeless column. People who see me camped on public land on the edge of town definitely will. I'm fine with that. At least until society feels it has to drive me off.