Berliners are awkward people. You are nice and sweet to them, and they’re offended. The most friendly compliment they make, is “da kannste nich meckern”, you cannot complain. Like if the purpose of your life is to complain nonstop.
Look at this. A student at a Chicago performing arts school conducted an experiment. She just told people “you’re beautiful”, and recorded their reaction. It’s such a nice panorama of people getting happy in an instant. She said, “ I was simply filming beauty and this is the result. Here it is.”
Imagine that in Berlin. People would declare you crazy, call the police for a violation of their privacy, or they’d think – guess what – you’re American.