Why is the their a media driven push in black/non black couples?

All the time now when I see a black person in a tv show or a movie now a days, he(or very rarely she) have a latino/indian/white partner.I am not racist but its like putting women who look black on tv is a crime except if they play a non romantic role. Why type of message does that send to little black girls who see these shows and every mainstream shows a well to do black male with a white women or one that is non black? do they take this into account, I have read stuff on how the brain can pick up on subliminal messages and it can have an effect on you wiht you even noticing. Its send a negative message that black men desire women that are not black and when they get rich they don't date black women, which is not true. i think its damaging to the self esteem of little black girls.