Interesting point in the Slate Fray on Schiavo by Thrasymachus:
Slate Magazine: "Ah, but why wouldn't I want to be kept alive in that condition? Isn't that the fundamental question that divides the two camps on this issue? Put a certain way, Johnson's argument is the very soul of reason: If I ever end up in a persistent vegetative state, then either I'll end up unconscious and won't care a bit, or I'll have some rudimentary awareness and won't remember anything but being in a persistent vegetative state, and will therefore have no desire to die. So why not just keep me alive? What's the argument for death?
Part of the 'argument for death,' I suppose, is dignity. I don't want to end up lying slack in some bed, making random twitching expressions and having my friends and relations consider it a 'red-letter-day' when my glassy eyes appear (perhaps) to reflexively track a balloon. But again- why should my concern for my dignity now have any bearing on how I'm treated then, when I wouldn't care about it a bit? Isn't that just vanity?"
Other than vanity, which might also be called the "yuck" factor, there are better motives for accepting death in such instances: ending the ordeal for relatives and friends, allowing them to get on with life; ending the burden and expense for caregivers and the community; and finally, making a "good" ending.