I have a few ads that Google considers "adult". I have a modified country list where I left out countries that have been known sources of click fraud and certain other countries where I thought the ads might not go over too well.
However, even if Google has such a policy, I don't think you need to worry about it much. Google simply won't show them in those places if there on some sort of "banned" list.
I'm quite surprised about Germany though. I mean, I leave off Saudi Arabia, Singapore, Vatican City and a few more, but not Germany!