i think everyone is overlooking an important part of this. you're saying you find it humiliating/degrading,"because a face is different than a vagina. my face represents myself. it's the symbol of myself to the world." i think of sexual ejaculate in a fairly symbolic way, so i am not offended by it. for me personally, i find it highly erotic and romantic. our faces are the image of ourselves to the world, so what could be sexier than a person orgasming to the sight of only your face? i don't find that humiliating, i find it to be highly personal and special. sometimes much more so than someone reaching orgasm because of a sexual organ that is my own, but does not uniquely represent me as a person.
i honestly don't care what people do in their own bedrooms, but i do get offended when someone says that i don't fully understand my own sexual motivations.