Costco, a discount shopping warehouse, carries more than huge boxes of Cheerios and Tide. It offers a limited selection of seasonal merchandise, like basic camping or beach equipment, at the kind of reasonable prices this mega-store is known for. It also carries industrial strength sheet cake - the kind you need to handle a crowd of indiscriminate but very hungry young ball players or birthday celebrants. If size is your goal, it may offer the best value in town. Shoppers must be members to shop here. The Costco website has information on joining.