Years ago I lived with a German woman who found it confusing that we British were always saying sorry. For example if someone ask us directions and we don't know, we say "I'm sorry, I don't know" and she would say "Why are you sorry? Its not your fault or your problem".
I was dashing from the train to the bus, when a boy who could have been no more than 14 asked me if I had a light. As a) I didn't have a light b) even if I did, I wouldn't have given it to someone underage, and c) I was rushing for a bus, I merely said "no". To which the lad replied "You should say 'Sorry no' not just no".
The cheek! I could begin to see that my old flatmate had a point.