Back to supermarkets, I hate it when I've shopped, paid, bagged, and am trying to leave, only to get stuck behind someone walking at snail pace, and taking up the whole aisle.......let me ouuuuuuut.
Same thing at the petrol station, when there's a queue of cars, and the person at the pump has filled, paid, and is sitting in the car doing God knows what, whilst everyone has to wait for them to move.