As a consumer, you can use cards for payment more or less everywhere you go, however, it is not certain that the card can be used for all purchases. When a customer pays with card there arises a card transaction fee charged to the merchant. This is a big problem for businesses where transactions with small amounts are a large portion of sales. An observation at the beginning of this study showed that seemingly similar merchants have chosen to solve this problem in different ways. Some merchant?s refuses card purchases below a certain amount, while others accept card with any purchase.