I have a few ideas. 1) It could be an attempt to joke around and have fun 2) People are just being assholes 3) It could be the view that girls are not all that great at video games/ not as good as guys (I play borderlands 2 with my gf from time to time and it's a bit of a slow process. She is good at AC and Dragon age though) 4) Teen guys hoping to see more than they will until after High school.