I've been on both sides of this...as a deliverer of services, I enjoyed the benefits of making it easier for my patients to pay me "right now" with a credit card, but it did bug the hell out of me to pay the fees. It cost me a fee, but there was a benefit. One thing I found, at the end of my career, is that as a merchant, you don't know what fees you've agreed to. As the CC companies compete with each other, offering bigger kickbacks to the customer, they would pay that out of the merchant's hide, without the merchant knowing that that he/she is paying 3.5%, or 4%....
As a customer, I enjoyed getting 1 or 2 % back. Of course, any kickback I got for paying business related bills with my CC I always declared as income, so I paid my proper share of taxes. I'm sure everyone does this.