In addition to jake's point, retailers have figured out that their consumers are stupid. So the retailer advertises the one doorbuster (only 3 units available at each store), and then keep everything else regular price or even RAISE prices. Then the hordes sweep in and the buying frenzy commences without any thought. Retailers don't need to offer deals on BF anymore because the legend of BF sells their product for them.
Oh, and the increasing importance of internet sales "cyber Monday" drives down the importance of BF.