I can answer this for you. Because in many states and/or nations, the age of consent laws have been different for opposite-sex & same-sex relations. It's considered another form of antigay discrimination & is a high priority at least amongst international activists (especially since many nations which have long-since repealed sodomy laws still have disparate age-of-consent laws - usually 21 for same-sex & 16 for opposite-sex - as their only remaining discriminatory statute, aside from marriage).