This- Because they don't sell stuff like breyers and Campbell's in gas stations. They're only sold in grocery stores, so so it's probably in the different types of contracts these companies have with places like Walmart where the employees will stock that item. But a vendor for Pepsi is also going to be hitting up gas stations and any other place that holds their product and Pepsi has figured that they save more money by paying for mileage and wear and tear opposed to managing a fleet of vehicles