Don't you hate it when you hold the door open for somebody who doesn't even acknowledge your existence?
Even worse for the eternally polite is the moment when you've just stepped through the doorway and entered the building and see somebody walking up to the door
Are you supposed to turn around and open the door for them too? Apparently only if they're really attractive...
Shaun Micallef of The Micallef P(r)ogram(me) explored this very dilemma a while back in the comedy sketch “Polite Distances”, proving politeness is often a ridiculous affair.
-Via Laughing Squid