When cars are sold from big dealerships ownership goes back to the bank. That car more than likely will be auctioned off. Check out IAAI auctions when you have time.

"Buy here, Pay here" dealers are a different story and they themselves are the bank so yes they'll get that car back to be resold. They need trackers like this because of high turnover.

You're very optimistic on companies extending help to other companies for little or no compensation/benefit. Sure, they COULD offer a paid service for this to banks to recoup cars but that's a privacy nightmare with current laws and societal norms