If you look at any McDonalds' ad they always emphasize two colors. Red and yellow. Yes, i know that these are the fast-food giant's colors that represent them, but they also serve a different purpose. Red and yellow are warm colors and for some reason they subconciously make people hungry. So you could absolutely say that every ad that McDonalds has every put out, has been inteded to press these so called "hot buttons" for consumers. Burger King plays the same game, they just add a blue ribbon around their logo to make it a little different.