German law essentially establishes a citizen's right to deny publication of an image/recording etc. if that citizen is depicted recognizably.

Exemptions are provided for cases like you snapping an image of a building or a group of your friends while I am just passing by (i.e. I am just incidentally part of the picture), or police mug shots.

I, too, am seeing that technological developments change our assumptions of privacy and socially acceptable behaviour, BTW. I just wanted to point out that we as a society can also choose to prevent unwanted consequences if we deem them unacceptable.