I'm not sure I entirely see the issue here.
What's wrong with moral relativism? It seems to me that an arguement against moral relativity is an argument for a universal morality, i.e. God/religion. Surely this is a stretch, but what's the alternative?
Might, seems to be the opposition here. Where might is always the moral right.
On an episode of "Star Treck the Next Generation", Picard and crew came upon a civilization of people who euthanized they're old people when they reached a certain age. It was looked at by these people as a celebrated occasion, a taking the next step. A party was held in the person's honor the evening before the euthanization, there were drinks, music, dancing and laughter.
Now as you'd imagine this whole idea didn't sit well with the enterprise crew, what with they're western American ideals and vision of life. The main character of the story was an old man who became highly respected by the crew, (for reasons that are not important here). When they learn that in just a few days he will be "PUT TO DEATH", they are appaled. Understanding that this is they're cultures way, they nonetheless try to reason with the old man and his family that he doesn't have to die. However the western spin eventaully falls upon deaf ears and the crew looses the battle.
With respect to the euthanizing culture, the story played on the logic that, at one point they simply took to this course of action due to the issues that came about in caring for the elderly. The practice had become so much a part of they're culture that no one saw anything wrong with it, and in fact looked forward to some respect to the occasion.
Certainly if a homogenous society is our goal, then pockets of differing moral ideas is a bad thing. But I find it damaging intellectualy to suggest that there is a moral right.
And what is good, Phædrus,And what is not good...Need we ask anyone to tell us these things? (Pirsig, ZMM)