It's cultural. One thing that drove me absolutely crazy in America is the checkers in stores constantly asking me how I am and wanting to be be pleasant. I'm not their friend. My ego doesn't need patting. I don't know them from a bar of soap, and no other country in the world obliges checkers to say be 'friendly.' It's acceptable to greetsome, check them out speedily without a word, and move on to the next person. So much easier and less stressful.