When people get a chip on their shoulder because of their age
Seriously though ... people who deliberately straddle two spaces in a car park so no-one gets close enough to scratch the paint on their fancy Alfa or BMW, or people who accidentally straddle two spaces because they are too lazy or arrogant to park carefully, or people who park in disabled or parent-with-child spaces when they are neither disabled nor accompanied by children ... all in all, I seem to find car parks distressing.