While there are some differences in German restaurants that might not always be appreciated by an expat, there is something that I do really like: they usually don't play music, or if they do, it's not loud and annoying. It's so refreshing! Going out to eat is seen as something special and it's meant to be a time to enjoy the company of one's dining partner and not have to shout over the soundtrack.
I was reminded of how much I prefer having no music in the German restaurants on Friday when a friend and I met for dinner at an American restaurant on the air base. The music was blasting and even worse, it was country music (the only type of music I dislike). I was about ready to politely ask the staff if they could turn it down when they did without prompting. Phew! It made the rest of dinner so much more pleasant.