Comment by Steve44

> This bit of randomly swapping freeway colors between brown and white seems to be a common theme.

It looks to me that it's to do with contrast against the surroundings. The build up areas are brown and the roads through them are white, when the roads leave the build up area they change to brown. This contrasts against the white background giving a visual continuation of the road.

The brown sections of the road are also thicker, perhaps that indicates multiple lanes or even possibly different road surfaces.