Providing discounts for cash, as gas stations do, was legal prior to 2013 (and remains legal to this day). In 2013, charging customers a clearly-notified fee for accepting credit cards was authorized for all merchants; most simply choose not to.

> In 2013, charging customers a clearly-notified fee for accepting credit cards was authorized for all merchants; most simply choose not to.

The federal ban on charging fees was lifted, but many states (including New York and California) also still outlaw this at the state level.

In addition, merchant agreements often prohibit it - for example, merchants that take American Express cannot charge fees for any transactions, even the ones that run on Visa or Mastercard.

In Australia I get charged separate CC fees when booking flight tickets, concert tickets, many filling stations, some food / hospitality businesses, etc. Surprised that's not normal in the US.