The German psyche is impregnated with the urge to snoop.
A country where is is the norm for bin police to go through your rubbish, where 'anzeigen' is ingrained, in that if you cut your grass on late in the evening, put washing out on a Sunday, have a small barbecue on you balcony at the wrong time, allow you dog to bark after nine at night (true) there will always be someone who reports you the the authorities.
It's worse in the old East Germany where most over 40's have Stazi ingrained in them, but in the old West Germany old habits die hard.