Carper, noun, one who complains or finds fault querulously or unreasonably. Could also be someone who fishes for carp, I suppose, but I just searched a few hundred thousand separate historical sources and it's not attested anywhere.

[Cortana: like having a dictionary that sometimes calls you an idiot.]

Anyway, probably not smart to get too literal on any of this and assume that last clue refers to an actual sanitation worker. What about that Superman guy? He ever do anything that could be described as taking out the trash?