KNOXVILLE, Tenn. -- Pilot Travel Centers, which says it is the largest over-the-road diesel retailer in the U.S., has become the latest truck stop chain to stop accepting Visa and Mastercard at the pump.

Now, customers must go inside and pay at the fuel desk.

Pilot said it took the action to stop hemorrhaging "significant" quarterly losses due to chargebacks.

Chargebacks are the process by which credit card banks bill merchants after a cardholder claims either fraud or incorrect charges. Chargebacks are used when credit card fraud occurs, and occasionally during "friendly fraud," when a consumer uses their card but incorrectly reports it as a fraudulent charge.

If a customer uses a credit card and disputes the charge or the amount charged, Pilot has little evidence to fight a bill from the card company, said Mitch Steenrod, senior vice president and chief financial officer for Pilot.

"If its done at the pump terminal, I cant prove it because I dont have a signature, so theres no way to stop it," Steenrod told a recent interviewer.

"(The media) would like to hammer on Pilot . . . for not taking these cards, but it isnt us," Steenrod said. "The credit card companies give you rules youve got to follow, operating rules, and theyve got the latitude to financially force you to follow the operating rules. Thats why we have to do what were doing."

Flying J came under fire from customers in May after announcing its ban on Visa cards at its pumps.

Steenrod said Pilot is working to develop an alternative solution to pay at the pump. Until then, Steenrod acknowledged that drivers will probably be frustrated by an inability to pay at the pump with Visa or Mastercard.

"Theyre mad and they should be," said Steenrod. "Ive talked to Visa and explained to them that while you think youre penalizing the merchant youre really penalizing the customer. Now, their transaction is significantly delayed and theyre infuriated. In reality, the credit card companies are doing a disservice to the consumer."