(Murderhobo, shortening of "Murderous Hobo", is RPGnet's neologism for spring, referring to rootless PCs who kill things and take their stuff with no moral dimension.)
So there's a thread over yonder Are the PC's a force of good? from a long-time RPGer who has never seen a game where the PCs aren't a bunch of self-serving pragmatists or out-and-out psychokillers.
If this were the case with me and gaming... I would likely not be gaming. If I want to see wall-to-wall self-serving pragmatists, I have politics for that.
I have no interest in a murderhobo game. I've had and seen a thankfully small number of players bring the murderhobo to games where it doesn't fit, and these tend to be game-killing disasters that are only entertaining as GMing war stories. This is one of those make-sure-we're-on-the-same-page things.
I've played the odd emotionally dead PC here and there, and run games that are about questionable morality, but they're about that, not defaulting to it. My default setting is trying to do good, and hopefully succeeding more often than not because my universes tend to be on the side of good.