Finding someone to have sex with you is hard enough, let alone trying to explain to them your alien tentacle fetish. For that reason (read: we don't want our lovers to run away from us in fright), we tend to downplay our kinky fetishes and desires when we hop into bed with someone.
You're f*cking along, minding your own business in missionary position, when all of a sudden you shriek, “DADDY PLEASE IMPREGNATE ME!” Now, your partner (who does not understand your incest/leather daddy fetish) will think you are 99,000 kinds of cray. So what's a girl to do?
In a perfect world, we'd all be able to communicate our hopes, sexual inklings, and *legal* desires to our partner without shame or embarrassment, but alas — we live in a world of blank awkward stares and WTF mumblings. So instead of finding lovers who will embrace our kinky kinks like mature adults, we must shout our weird fetishes from the Internet message board rooftops! “I WANT TO HAVE SEX WITH THE FEMALE FORM OF JIM CARREY'S “THE MASK!” *echoes into vacant oblivion*