I have seen tons of these people camped out in the desert from Quartzsite down to Yuma. Some on the California side of the border. When the Summer heat comes they head North.
The Quartzsite crowd are “snowbirds” fleeing frigid snowy weather. A lot of them store their RV’s there and fly in or drive in with their Jeeps and such. I wouldn’t assume they’re living the nomadic life. Some are, certainly, but not even close to a majority.