Classically, breweries would have maybe three main products at different price points, all variations of the same style, differentiated primarily by strength, and secondarily by the amount of adjunct and/or hops used and the quality of malts and hops used. The tiers were categorized in the industry as "price," "premium," and "super premium," with Budweiser being AB's premium, between Busch and Michelob. The "light" products weren't even in the main line, they were niche, specialty products, just as were extra strong or seasonal offerings. Obviously, in this case "premium" means something different. These are the biggest sellers (IIRC these are the top four nationally, Budweiser being number four.)