I also hate the black-and-white morality. And I definitely hate the way the Warhammer setting treats corruption.
This is mainly because I'm a Christian. I know that seems odd, because a lot of this stuff is based on Western Christian morality stuff. But the thing is, it's usually based on a popular perception of it, not what it actually is.
The huge thing I hate about Warhammer corruption is that outside things can corrupt you, and you have no choice in the matter. I remember in one session, my character found a chaos gem and instantly gained a bunch of corruption just by finding it. I hadn't interacted with it. I hadn't used it. All I did was look at it. My character became twisted by chaos, not by anything I did, but just by seeing it. I hated that.
See, the thing about Christianity is that it says we're all broken, but we get to choose. We can choose whether to participate in evil, whether to worship things other than God. Christianity makes clear that nothing can save you apart from God, but up until the point of death, you can always choose. Yeah, non-Christians can do amazingly good things and refrain from participating in evil–that's their choice. It won't save them, but they're free to do it. Everyone, Christian or not, is free to resist temptation and evil.
So I hate when they don't have that choice. An orc, despite being a totally sentient being, is just evil and only ever does evil. Stuff like that.
Oddly enough, though, even in early D&D stuff, good people could choose to become evil. Even elves: dark elves–elves who have chosen to follow evil–have been there all along. But evil things don't generally get the chance or choice to do good. There have been exceptions, like Raistlin from Dragonlance, who turned to evil and then redeemed himself. But by and large, a dark elf will always be a dark elf and an orc will always be an evil creature. I don't like that at all.
But as beholdsa said, it does make justification for the mass slaughter the PCs generally do. Which is another thing I don't really like about fantasy genre: often, the main characters behave like sociopaths.
It's action movie syndrome: the main character can delight in killing hundreds of guys who are opposing him, even make funny quips as he kills them, and it's all good because he's the good guy.
Sure, some of the mercenaries he slaughtered were doing it because that's what they wanted to do. But a lot of people take violent jobs where they do evil things just because it's the only job they could find. Others, because the money's just too good, and they quickly grew numb to it.
I remember watching an interview with an ex-thug who worked for human traffickers. He abducted women, even raped them and helped others do so. He said he didn't want to do it, but the money was just too good. And after the first few women, you just stopped feeling it. Essentially, he was trapped in it–but he got to leave it, too. Even trapped in it, he still had a choice.
And that's something you don't see in most combat-oriented RPGs and action movies. You don't see the drug dealer who is doing it because he has a family to support and that's the best way he can make sure they have the money they need. No, he's just random mercenary #28, who gets blown away while he tries to surrender, because the hero's fed up and he's not going to let stuff like this happen anymore!
Yeah, I don't like the morality systems in most RPGs.
It still seems odd to me that people might see torture in fantasy as a gray area. It's always seen it as solidly to the evil side through and through. But I could be the odd man out here.
re: Some things being objectively evil or good:
I really really dislike it when the game takes an objective stance on what is good and evil. I want to be able to come up with an interesting worldview for my character, and not be told that his views are objectively wrong. And I want to be able to discuss this with other characters - PC or NPC - and not have everyone know who is really “right”.
It doesn't really matter what I think is right or wrong in real life, or how plausible I find the list of objectively evil things to be (I think in practical terms, torture is wrong 100% of the time; while I can easily think up likely scenarios in which Necromancy would be justified). Even if the list of the “objectively evil” is entirely plausible and in line with my own moral beliefs, I dislike it. I find knowable, objective morality to be both boring and a strain on suspension of disbelief.
re: Some classes of being being objectively evil
I'm not a huge fan of this, though it doesn't offend me exactly. Moreso it's a practical concern: these tend to be the less interesting types of adversaries out there. I'd rather be opposed by a noble from Grandeur with his own unique mixture of nationalism, economic self-interest, and pride, than by a zombie, demon of Khorne, or kill-o-tron 9000. It's really about the range of action possible - when you take away somethings capacity for good or any kind of positive emotion, you take away a lot of options for dealing with that threat. And even more importantly, when something is knowably evil, you take away a lot of the suspense that comes from not knowing what it's motives are.
I don't think torture is ever completely acceptable, but it does get used, even by the good guys.
The treatment of Gollum by the heroes in Lord of the Rings, for example, gets rather rough at points.
“I caught him, Gollum. He was covered with green slime. He will never love me, I fear; for he bit me, and I was not gentle…I deemed it the worst part of my journey,…watching him day and night, making him walk before me with a halter on his neck, gagged, until he was tamed by lack of drink and food…”
“The truth was desperately important, and in the end I had to be harsh. I put the fear of fire on him and wrung the true story out of him, bit by bit…”
While these are not directly torture, they aren't exactly civil by modern standards. The movie went a bit further with the men of Gondor beating on Gollum for no reason.
From Warhammer 3rd, torture wasn't just reserved for evil Chaos, but for all sorts of crimes:
“The price of discovery is usually the mutilation of the forger’s hands, and a period of torture as the authorities try to learn what jobs he performed in the past.”