I gotta ask, what's wrong with Judæo-Christian ethics and win-win solutions? What's wrong with getting along, with doing well by doing good, with honestly trying to be pleasant to others? Would that be the end of the world?
To go further: I don't really see a point to any negotiation that isn't a positive-sum game. And not for ethical reasons! To me, it doesn't matter if I or someone else gets more of a pie, because it's still just one pie and talking won't make more of it, so any time spent negotiating has opportunity costs that lower the aggregate ROI of our combined pie-slices. Negotiation spends pie. If the goal is to get the most pie, why waste time negotiating that you could be spending making pie less scarce?