It's silly little annoyances really. Unwashed out tins of things - or rather tins with an inch of old dog food to beans left in the bottom. Beer cans with off mouldy beer still in them, that tips down your sleeve as you put them in the bag. Boxes that seem really full of stuff when you pick them up, but it turns out to be half a tonne of soggy old carrier backs and cardboard, and the half paving slab they leave in it to stop it blowing about. Box juice running out of the drain hole down your leg.
Actually, all that is minor stuff. It's the grumpy people that are worst, the ones that blank you because you are obviously untouchable, or who complain because you won't take the stuff you've told them you don't take...
But the guys I work with make up for it.
In the other job, well, sometimes I'm forced to try out brand new bikes of all sorts. Such a drag....