I am always surprised this is an issue. As many said, it's a game, go with whatever you want, for whatever reason. It's no ones business why. When DDO first launched, my wife played a female human pally. When we joined PUGs, people were surprised she really was a woman, and not a man. I use female avatars in some games for meta reasons. As others have said, it could be better voices or modeling. In some games (like Titanfall), I use a mix of avatars to help me quickly find the loadout I want.