I'm an American who lived in Germany for a few years as a child and visited many parts of Europe later and I've always thought of Germans as being a friendly people (ex. when we'd just moved to Germany, my father's German wasn't so hot and he took a seat in a train car that was more expensive than the ticket he'd purchased warranted. While the ticket guy was trying to explain this to him, a random German just paid the difference between the two tickets; that doesn't happen too often over here). Now's it's true that that friendliness doesn't always seem to extend to people that aren't white and/or don't have German surnames, but within those bounds, I'd say they're actually friendlier than we are, particularly with strangers.
However, I'll admit that service in stores/restaurants might be an exception. I've found that on the average, a "service person" in Europe is noticeably older than his American equivalent, which probably doesn't help anything and most European countries seem like terrible places to be poor; a cheap house over there is a hovel and a cheap car is little more than a golf-cart. I don't think being surrounded by things you can't afford improves anyone's disposition.