In reply to the original post, yeah, I think it's inconsiderate. It's not illegal, though, so the only thing I really do about it is choose not to be nice to the players involved later, if I happen to end up in a situation where I have the choice to be a dick towards them, or be nice instead.

If I happen to run into a few dudes I know to be nice who are wiping to some stuff when it's at like 30%, I might actually try to hold their mob till they get all rested up, instead of killing it and taking the drops for myself.