Yes, gods and petitioners care about the desecration of corpses. A low-level necromancer may only be able to use the husk to abscond with the body and the petitioner might never know, but more powerful magic could possibly drag the individual out of the afterlife and back to the material world (creating things such as vampires or other other intelligent undead - possibly even thousands of years after the original individual has died).
Assuming the body is still thousands of years later, the petitioner has long since become some kind of celestial or fiend. So if you assume that Create Undead calls the original soul back into the body, you are using that spell to summon an outsider and then stick it in a corpse. So now you have a precedent for using Create Undead to summon outsiders (which is a completely different school of magic). And said outsider is probably going to rip its way out of said corpse and kill you for the embarrassment.
And while the Negative Material Plane is itself a neutral force, it is a force of hunger and devouring. Undead created by it, as one might see from myths and story are creatures driven by uncontrollable hunger and negative emotions inspired by that hunger. Liches tend to hunger for knowledge and/or power. Vampires crave the blood of the living. Ghouls crave flesh of the living, spectres and wraiths the very life breath of the living - and so forth. We even joke about it with zombies and "braaaains". (Though I've not seen stories of "skeletons" hunger - I guess they're the exception, famine spirits too far gone to consume anything). Necromancers who create this stuff then are essentially seen as the creators of unnatural famines - they are inflicting a sort of misery for their own aggrandizement.
Actually, according the to MM they don't need food (e.g. undead do not eat, breathe or sleep). They just kill and eat people
because they're evil jerks.
This argument boils down to "the soul isn't in there anymore, use the flesh" and it ignores a number of variables.
1. Whatever religious, societal or even what the soul/former person would want done with the body. If a corpse in our real world is dug up and mutilated for pretty much any reason, especially without the person signing an organ donour card then it is a pretty heinous and illegal act. It is equally wrong if it it not dug up, but done after death but that is beside the point.
2. It ignores the religious, societal, etc., concerns required for afterlife. The Egyptians believed that a bounty was required to buy a station in the afterlife. Vikings were given weapons for the afterlife. Why would this not apply when you know there is an afterlife compared to belief in one (as in real life)?
3. Consent - already covered a little - but you are basically using somebody's body without their consent. This is made worse when you can literally contact them. Just because they aren't using it doesn't mean they would like someone else to make it walk around and serve them in the most degrading ways possible. Especially with known symptoms of: hunger, kill/eat innocent people, have no will of its own, forced to obey the creator/master.
Oh, I'm all for the rights of the deceased. But they only own the body while they are alive, and can sell rights to their corpse. After they're dead, the body belongs to any surviving family. If there is no surviving family, the corpse isn't owned by anyone.
But those various beliefs about the afterlife are quantifiably wrong. Anyone who dies immediately gos to the afterlife that fits their alignment. Their funereal is irrelevant to that.
People believe reanimating corpses is wrong because of social taboo. One could easily have a society where this isn't the case, where necromancy is a recognized as a legal profession and most people have zombie butlers and look forward to existence as a undying soldier that will defend the homes and liberty of their descendants. In such a society, dangerous undead would be seen as no different from, say, any other extremely dangerous man-eating monster like mindflayers, and you might even have people campaigning for zombie rights and zombie marriage.
Or you could sidestep all these moral issues completely by only reanimating evil people, because being EEEVIIL automatically negates all rights to life, liberty, property and the pursuit if happiness according to D&D's warped system of morality. I doubt the villagers would complain if everyone one of them had a zombified goblin slave-butler that had absolutely no purpose in unlife other than following their orders (and no, D&D zombies don't eat people, they just follow orders, like in voodoo).
Actually, unless I'm vastly mistaken, when you animate a corpse you do attach the soul to it. So much so that as long as they are walking around they cannot be resurrected without first destroying their undead self.
That isn't actually stated anywhere in the rules. Even the text of true resurrection does not actually state that being undead prevents resurrection (you can cast the spell on an undead to cure them), it only states that undead creatures that have been destroyed are valid targets for resurrection, not that the undead
must be destroyed before the original person can be resurrected. Hypothetically you could use the spell to repeatedly resurrect yourself and animate your previous corpses as ghouls or whatever. Which brings up the question of what soul they are using if your soul is in your own body.
Wars have been fought for centuries under the argument that certain people are simply lesser for arbitrary, nonsensical reasons. In this case, there's a concrete, completely objective reason that the vampire is, in fact, inherently superior to the cattle.
Or, if that argument doesn't move you, the vampire has to eat. Would you fault a wolf for killing sheep?
I would fault the vampire. He doesn't actually
need to feed on humans in particular (or at all, barring the sustenance rules in
Libris Mortis), and can just feed on animals or evil humanoids or use magic to create substitute blood that tastes better. Humans are equal mentally to vampires because both are capable of philosophy. Any vampire that feeds on humans is just being a jerk.
Here's my take on the subject.
That is very good reasoning for why undead would be inherently evil. Sadly it's not supported by the RAW.
