This is something I love about living in germany, actually. In the UK (where I was brought up) you're very used to the kind of absurd situations that develop from common sense not being applied to rules. If you talk to somebody in a position of authority, you absolutely expect them to pick the least reasonable, least constructive application of any rule they have at their disposal to ruin your day.

I don't know why this is so different in Germany. I've more often observed the inverse - where people (mostly well-dressed middle-aged men, for whatever reason) are extremely rude and condescending towards secretaries, ticket collectors, etc.