Costco also sells roast chickens for $5 (or, at least, they do where I live). Their rotisserie-roast chickens are twice as large as the chickens at any other store for half the price, and as a result they tend to attract a small army of people hungry for amazing chicken at a good price point - people who then see all of the other goods in the meat department and are likely to buy at least a few that catch their eye.

It's a common play by smart stores; they'll have a few items that are such an uncommon value that they generate buzz that brings people into the store, thus boosting sales.

It's a good move for a business. It's just not the type of good-for-business move that is easily visible on a balance sheet. How do you explain to a short-sighted CEO, who has a spreadsheet jammed up his ass showing that Product X has razor thin profit margins, that the real value of Product X is that it increases the sale of Products A thru Z by two percent?