In Norway the plates to owner database is public, and you can either use the free government service or for profit ones. To look them up.
Basically ownership of vehicles is not viewed as private information. So it isn’t covered by privacy legislation. But tracking where the car is, that is covered. That doesn’t stop, speed traps reading car plates, nor parking tracking with cameras. But that info can’t be sold for other purposes.
Interesting. That's not the case in most countries as far as I know - there isn't a way to look up a car owner from the plate (for free or for pay; law enforcement of course can look it up).
Income in Sweden is IIRC also public, perhaps in Norway too - and that's also private almost everywhere else.