Well at least someone picked up on the real reason for the cash vs credit bit.

The point of the article was the alternative fuels.

It was quite common years ago to have a cash and credit price. The difference was that they only posted the cash prices. In fact when they started to phase that out you would see boards that said Cash Or Credit Same Price.

The reason for the difference is the fee the credit card company's charge the vendor for use of their card services. (usually <= 1%)

 

Except for AMEX, which charges up to 3% (which is why a lot of places don't take AMEX) (darn it)

 

Well there's that and the way AMEX handles disputes.

When we had customers dispute a charge on their card, MC or Visa would start an investigation and then reverse the credits if necessary.

Amex took the money immediately and then investigated and would re-credit the money if necessary.