What I hate more than dumb pedestrians is people in cars who stop for me when I'm riding. If I'm coming up to an intersection on a small street with no light or stop sign and they stop anyway. At that point I have to pretty much stop myself. Then they signal that I can go first like they're doing me a favor when they could have been way thru the intersection before I even made it there.
Oh and last week it was great when some hillbillies in a truck used their walkie talkie megaphone speaker gadget to tell me and my friend "Get on the ****ing sidewalk." Thanks guys.