I have heard others talk of many things that your comments are related too. And the issue I was speaking of before is also reflected in Germany and in other countries as well. For instance, the Korean population outside of the bases that barracked the 2nd Infantry Division were not so friendly toward the US troops because those troops didn't behave themselves as well. Those guys really didn't care so much about being "good ambassadors" for the US. They wanted to get drunk and get laid and that was about the sum of it. In Seoul we had a different problem because of all the Korean Universities and the protesting that their students seemed to never tire of. So soldiers were treated OK in the shopping areas, it's business, and rarely had real problems as long as they didn't get caught up in a riot. But my Wife's family lived in the heart of Seoul far away from any base and I was never treated poorly by the community there. They weren't crazy about me, but they never were hostile towards me or my wife when together. Of course, as others have said, big cities all over the world are what they are and not usually known for being openly friendly on the streets.Yeah, I've noticed in the military base areas they also tend to teach American-style English rather than UK-style. When they hear English, they want to try theirs out. In Bamberg, I've encountered several locals that sound like they grew up in the US, but have never even left Germany. They even use and understand the same types of slang. I'm sure American TV and music probably affect that, too. Even though that base is closed now, there are a fair number of American ex-pats living in the area.
Munich has a massive American ex-pat population. I don't think I've ever gone more than a half hour without hearing someone speaking English anywhere near there. I know only a little German, so when my wife and I are wondering (aloud) what a sign or ads says, a friendly answer and explanation has been given without a request many many times.
I've had similar experiences in Dusseldorf, which oddly has a huge Japanese population. I think English is used as the common language there.
One thing a lot of people don't realize about Germany is that as a united country it isn't that old. I'm not even talking about East/West either. One reason states like Bavaria seem so different from Berlin, Bremen, and Saxony is because they were different kingdoms until the 1800's. There is quite a bit of social strife between states that's pretty similar to the type we have in the US. In particular north vs. south and the former East German states.