The whole objection to miscegenation, the belief that it is somehow immoral for people of different ethnic groups to marry, reproduce, or fool around, has no legitimate basis. It is just a prejudice based on xenophobia. So, movies show couples of mixed ethnicity because, in the first place, this is what the world is like (and let us not forget, even Strom Thurmond, who warned us about Negroes getting into our swimming pools, secretly fathered a daughter with a black woman) and in the second place, it is what the world should be like. When people form friendships or even romantic relationships with people of other ethnic groups this shows that we as a society are overcoming racism. We are all human beings, believe it or not. We belong to one species. Miscegenation is an imaginary offense.