Bog trolls might be excused their actions on the grounds that sitting in the toilet for five hours a night can't bring a lot of job satisfaction, except that it's not a proper job and no one wants them there in the first place.
Me: No thank you, I can manage to do this by myself.
Bog troll: (indicates tray with assorted change from previous mugs) Fair enough (looks at you like he might have already killed your family)
Drunken reveller A: Taxi home?
Drunken reveller B: Nah man, let's walk. I broke the seal too early and spent a tenner on bog trolls already.