It's obvious HBO is aiming this ad at the casual fan - someone who would recognize Stewart, Kahne, or one of the others pictured. They're obviously hoping to attract the interest of the "other" race fans to watch this event. Open wheel fans of most types(sprint and midget) already know of the Chili Bowl. It is the other folks that they want to attract.

And stagger, haven't Kasey and Tony won USAC midget championships in the past?