It’s pretty common to have unlicensed off road vehicles, especially in the mountain west. Farmers and ranchers often have at least one of these. There’s plenty of recreational users as well.
How many recreational users have private land in sufficient quantities?
You’ll sometimes also see small communities with private roads that allow unlicensed vehicles, such as retirement communities, but they often have their own standards for what is allowed.
* anyone with a few hundred million in the bank.