Unless you get the (superior) Hebrew National dogs that come in packs of 7.

In which case, to get an even number of buns, he’d have to buy 12 packs of 7 hot dogs and 7 packs of 12 buns, for a total of 84 hot dogs and buns. (Or remove 5 buns from each 12 bun bag.)

Edit: Which means Joey Chestnut could eat his new record of 83 of those dogs in ten minutes and have another left over for Steve Martin!