In accordance with at least one embodiment of the present invention a retailer may receive a request from a group of customers for a reward the group desires to earn by making purchases at the retailer. In response to such a request the retailer determines purchasing conditions the group must satisfy in order to earn the reward. The purchasing conditions may be determined based on, for example, a value of the reward (e.g., a cost of the reward to the retailer), a number of customers in the group, and/or a time by which the group desires to earn the reward. The purchasing conditions may be determined such that the retailer realizes at least a predetermined profit after the cost of providing the reward is considered. The methods of the present invention may be implemented at an online and/or brick-and-mortar retailer.