If you ask the producers of hot dogs and buns this question, you’re not going to get a really firm answer. The standard reply from meat packers is that they like to sell their product by the pound. A grouping of 10 hot dogs comes close to a pound in weight. The best explanation for bakers is that 10 buns would be at a higher risk of getting damaged during shipment than 8 buns. I guess the real reason is that no one really complains about this minor problem. Oscar Meyer says that of the 50,000 consumer letters they get each year, only 10 or 15 mention the hot dog/bun mismatch.