This is completely untrue. What you are describing is how Facebook has colloquialized the word "friend." The American concept of actual friendship is no different than the German or the Japanese one. A "true friend" is a pretty universal concept. Nobody mistakes a "FB only friend" for a true friend. There's no reason for you to bash Americans. Frankly you are unlikely to make meaningful connections with any other nationality when you're making cultural superiority judgements like that.