We could tell who you were by your haircuts.
It's always been that way...lol.
In Germany, we had another distinguishing characteristic: green license plates on our cars. It really made German drivers angry when I passed them on the autobahn.
During my last two years in Germany, I spoke the language well enough to earn quizzical looks from those I encountered for the first time. You know, "he looks like an American, but he sounds like a German." lol