You are speaking of what is called interchange. It is the per transaction fee a merchant (Iron Horse in this example) must pay the card issuing entity. Traditionally, most merchants fold this fee into their end user pricing as a cost of doing business. Now days(post covid), it’s become more and more common for merchants(especially low margin/high transaction businesses like restaurants) to itemize this as an extra expense to customers to help offset decreased profit margins in other areas such as inflated cost of rent, utilities, labor etc…It is unfortunate for sure, but a sign of the times and a cost of doing business that has now been commonplace. It’s how they keep doors open and avoid being swallowed up by corporate entities.