You say it's for a reason... but then you don't actually give that reason. What is the 'reason' you're referring to? Care to explain?
Why should monstrous races be an option available to Dms and potentially players? Because, for mortal races, evil is cultural not in-born; individual exceptions, through fluke of circumstance and opportunity, can and do exist, and it's important that they are allowed to.
That's where our opinions differ, I take a deterministic approach and therefore believe that monsters are inherently evil without any choice. Basically like orcs and trolls in Middle-Earth, they are evil because they were created by evil and are incapable of being anything else.
It's a matter of personal preference, I just happen to like my fantasy black and white and not in shades of grey.
