I assume you got your national ID card and register at the police station every time you move.
Registering with the police when you move is standard practice with all countries, USA included - you are required to give your SSN to every single DMV now to receive your state ID card/driver's license. They are available in every police cruiser. Are we going to split hairs over which agency runs the server the laptops in the police cars get to query?
That is not a very good argument. Why do the Germans need you to register at the local police station?