People that block the pump just to go inside and get whatever they're getting. There's parking spots right by the door...
4 cylinders with literally cut off exhausts that want to drive up and down my development late at night. The Wrangler with a cherry bomb muffler that drives by at 5AM.
People that can't seem to park between the lines.
Door dings.
Litter. Especially people that throw stuff out of their car window.
So basically, most people grind my gears.
Golf-related:
People that ride your ass when there's nowhere to go.
People that don't rake, replace, or repair.