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@mark @nowster mmm that's not really what I mean by temporary.
Dealerships do have a special dealer plate (which changes color every year) they can slap on any car to move them around or for test drives or whatever.
But at least in Illinois, the plate only serves to reference who the car belongs to. It doesn't stick with the car, it's the driver's property. So a temp plate is just a laminated piece of paper to serve that purpose between when the car is bought and the state issues a real plate.
@mark @nowster and every time the car is sold, the owner is obliged to take the plates off. If they're getting a new car, they can be transferred to the new one for a fee. Or they can just keep them as a souvenir. Or recycle them at registration offices or stick 'em in any mailbox.
If you wake up and find your plates were stolen you report them as stolen and are issued new ones. The state handles all of it and it's honestly surprising to me that that's delegated in other countries.
@hazelnot@sunbeam.city@TechConnectify @mark @nowster here in Romania it's even more ridiculous - thet technically belong to the car, but you're required to take the plates off and return them to the registration authority when you sell the car.
The new owner can then explicitly request to use the same number, and I think end up picking up the same plates that were dropped off by the person they got the car from but with an extra trip and paperwork involved 
@hazelnot sometimes it's nice to know that our government actually has a few things it's doing *better* than other places!