My pet peeve isn't concerned with drivers but rather people who stand in the "bike area" on the Metro train. These areas are marked for strollers, luggage and bicycles. not for JSA (just standing around).
Sometimes when I roll my bike up to the "bike area" the "standers" do move (most of the time there are seats available on the train too!) but other times they just keep standing there, pretty much oblivious or maybe it's territorial, I don't know.
Anyway, that's my pet peeve.
Rick / OCRR