Hussar said:
Way cool idea. Imagine what a conclave of these kind of drow would be like. Then have the party come busting in ready for bear. It would be like kicking puppies. Watch the paladin squirm as the drow burst into tears when he tells them he's going to lay some righteous gluteous prodding.
I love it. Nothing like playing on player expectations and sticking it to the meta-gamers.
Two thumbs up.
I think DMs need to be willing to alter fantasy tropes as fit their campaigns. It can have several good effects.
First, a DM can craft entire species and cultures to fit individual visions. For example, a world with many differetnt drow societies (much like the diverse human cultures of our own world) might be a much more interesting place to visit than one where an entire species is almost utterly predictable in its actions. (Edena, Lolth IS in some ways very predictable.... which is why a rival spider deity might get the upper hand. Particularly if they could offer a few practical things -- food, trade -- to self-interested drow. ("Hmm, more wealth for me and food for my offspring and myself --- and I don't have to put up with these priestesses. Hmm, maybe we can overthrow them and take their welath. Where do I sign up?"

)
Also, if "standard" versions of the races in the Monster Manual or other works exist, it might make sense to come up with good rationales and histories. For example, hostile orcs might be oppressed, have bad leaders, or have dark gods who try to install hate into them -- aided by orcish leaders. (Edena, as I recall, aren't there a small group of orcish pacifists in the Forgotten Realms who follow the teachings of Eldath, goddess of peace and water, who were converted from violence by the elves of Myth Drannor? )
Additionally, a DM can give players moral dilemmas. For example, if a character who has fought evil drow finds a neutral or even good community of drow who needs his help, how does a supposedly good character react. Does the character ignore their needs, or learn to put prejudice aside? So, I think a willingness to reconsider a few standard interpretations of creatures and classes might lead to a sense of wonder and mystery in a game. This can add to the fun of the players and the DMs. I think that good DMs can ask questions, and surprise their players every now and then. (Hmm, I wonder how a few PCs might react if they encountered a group of drow that treated them with respect, honoring their reputations as great heroes? At least it might shock a few complacent players.)