In quite a few episodes, including this one, whenever a filmed close up of food packaging occurs, the name of that certain food item is partially obscured by a "SALE" sticker.
This was one of seven episodes in which James Earl Jones added an unique one-liner to the standard narration under the opening credits. Here, the one-liner is "The people of earth sometimes divide against each other based on national origin or skin color. Of course, no-one else in the galaxy can tell them apart."