That still doesn't seem very private.

For a vehicle with a highly visible unique identifier on the front and rear? In my country basically every private carpark has ANPR cameras, the tech is dirt cheap now.

Particularly anywhere rural or off the beaten path

You wouln‘t really have the kind if hardware there. The communication relies on a multi hop mesh that would‘t work anywhere without sufficient coverage.

You do know you have a unique ID displayed on a big tab on the vehicle, right?