OK, how?
It just seems like to be a rather self-centred thing for the relatives to do. They can't even say "It's what s/he would have wanted", because it demonstrably isn't.
"They've suffered enough". They're dead, dumbass. Cutting bits out of them isn't going to make them suffer more. If the relatives said "We've suffered enough", I would at least appreciate the honesty, but my response would still be something like "Well they wanted to go through with it, and I'm pretty sure their wishes overrule yours".