1. A method for operating a reward program comprising the steps of: establishing or identifying a plurality of product categories; receiving from a customer an indication of consent to participate in the reward program; receiving by a computer system an indication of at least one selected product category; tracking, by said computer system, a customer's purchases in the at least one selected product category over a plurality of discrete purchase transactions for a given cycle of the reward program, which cycle has a starting point and an ending point, wherein the second receiving step and the tracking steps are carried out by a processor of said computer system according to software comprising computer-executable instructions on a computer-readable medium; processing a plurality of purchase transactions during said given cycle of the reward program in which said reward is accumulated but is not provided to said customer, said reward being accumulated over said plurality of purchase transactions in which said customer purchases at least one product in said at least one selected product category in each of said transactions; calculating, by said computer system, a reward for the given cycle of the reward program; and providing, at or after the ending point of the given cycle of the reward program, said reward to said customer which is based at least in part upon the monetary amount of the customer's cumulative purchases in the at least one selected product category after the starting point and before the ending point of the given cycle.