We sat down at the Stammtisch.
The waitress kindly told us that we should move. Then everybody in the place was kind of cold to us, until someone picked up from our conversation that we were from the US. The waitress tentatively asked: "Are you Americans?" Yes. "Oh, we thought you were English." All of the sudden the whole place warmed up to us, and they even brought us complimentary glasses of the house liqueur, which I can tell you was quite potent.
I don't know why they liked Americans better than English, and we didn't press the matter.