Been to three shops today, all of them had massive queues! I dislike queuing in shops. I don't really know why but I expect to be served pretty swiftly. Especially in smallish shops. On weekdays daytime. Bitter!
If I go to a large supermarket I expect it to be very busy so that's ok, I suppose it all boils down to one's own individual expectations. If I go to the post office I know it'll be busy so I'm prepared to wait, but they have several people attending so there's little the poor chaps can do. Same with surgeries, you expect that consultations may over run, and that's comforting because you'd want the doctor to take as much as possible with you when it's your turn.
I also dislike waiting for the bus, any bus. I think this is because you never know how long you have got to wait. I have no problems with trains for example, or coaches, bar five minus or plus minutes they are generally on time.
Random waiting I think is the issue. Some places you walk into you have no idea how long it might take, this could be because of generally awkward customers or inefficient and incompetent staff, or both combined which is a powerful mixture for the greatest pain in the ass waiting time.