"it's a bad moral choice, there aren't enough rewards for nuking megaton! you can get all those caps easy in the lategame! if you try to turn burke into the sheriff instead, burke kills him and he drops one of the best assault rifles in the game early!"
Having never played Fallout 3 past the first hour, that's what I figured the appeal was. Completely wackadoo unrealistic moral quandaries backed up by a binary system of karma, alongside a generous helping of environmental storytelling