I saw a comment (about Torchlight) where someone was annoyed that the only female player option was "white, long-legged, and busty", and faced with a character which would always be scantily clad, felt sufficiently unwanted as a player to leave.
I haven't played it myself but I get the impression that there may be more than one male player option - if so, that makes it much more obvious that the female is just an afterthought. At least, it would to me, and I'm guessing it did to that commenter as well.
The latest casual game *I've* been playing is something in the civ/strategy genre called Gemini Lost. It's cute, if clearly heavily derived from Virtual Villagers. One thing that's noticeable is that there's a fairly low number of human models, and the engine doesn't seem to include palette variations, so ALL characters of model X will be identical brunettes in purple dresses.
The weird thing is, there seems to be only one non-white model... a black male. Maybe two if there's another clothing option for him, I'm not sure. But there's very certainly no black female character, or anything else. Also, while the game forces you to pair up your characters to marry them off and breed them to produce a new generation of workers, the actual parentage of children doesn't seem to be tracked or matter for anything, including appearance... which is particularly noticeable when you've just started the game, you have only one black character, you've just married together two white characters, and they promptly produce a black boy baby.
If you're thinking enough about diversity to stick in one black character, why only one? It's not like they're actual characters where you'd need to do work to carefully develop the backstory of them, they're just Generic Villagers who're going to live and die at your command.