Because if you're comfortable with your sex, you don't really need a reason. The only people that don't pick girls while gaming are men with machismo issues or men that have homosexual tendencies and are ashamed of them. (By the way if you do have homo sexual tendencies, it is nothing to be embarrassed about.) You choose. Edit: Wait, if you mean they're Xbox avatar, then yeah that's a little weird. You would have to ask them, but I don't see a problem it's not like I hit on girls online.