Have you ever noticed that some gas stations list two different prices on their signs? The lower price is almost always for customers who pay with cash, while credit card users pay a higher rate. This price gap exists because gas stations have to pay transaction fees every time a customer swipes a card. These credit card fees can take a big bite out of the station’s already thin profit margins. When you pay with cash, the station saves that money and passes a portion of the discount on to you.