During the Great Bohemia Oscura Shortage of two or three years ago I went to several OXXO stores looking for it, and none of them had any beer at all. It was weird.I haven't found Soriana and other big grocers to be much cheaper on beer than Oxxo. Sometimes Oxxo has sales that are better. But, while I love to save money, when I stay in town I tend to buy beer and soda from the little aborrotes. They definitely have higher prices but I feel the money is going straight into the hands of locals rather than corporate coffers.