Are they supposed to represent a white family,

Why do they have a black and white background for the movie backdrop? Yes, Marcus and his family are black, but America Ferrera and her family were mexican, not white. A lot of mexican and black people deal with the same struggles in America trying to be excepted, but it seemed like they were supposed to be a step above Marcus' family. Also in the tuxedo shop when Carlos Mancina's character had on the white tuxedo and Forrest Whitaker had on the black tux. It seemed like they were supposed to represent a white family even though they were strong to their mexican roots throughout the movie.