Dollar General is borrowing from Costco's bargain hunt model, which generates predictable, high-margin income primarily from membership fees and provides a significant portion of its operating profit. Costco CEO Ron Vachris stated that membership is the most important product that Costco sells, with 60-70% of its profits generated from these fees. The warehouse club's "treasure hunt" model also drives traffic to its stores, as members don't know what they might find on any given visit. Dollar General has been experimenting with a new store format designed to make the retailer more like Costco. The company's CEO, Todd Vasos, also highlighted the potential for recurring revenue from a membership or subscription program. However, there are risks of adopting a subscription business model, including brands like Loot Loot, which filed for bankruptcy in 2012, and Loot.