I'm not sure how big of an issue that it is people are claiming. It's like a 3-4% issue.

If you're writing off 3-4% of what you charge for your labor, you probably don't consider it a big deal.

If you're baking 3-4% into prices of items you sell at brick-and mortar retail - because that business doesn't have high enough margins to just write it off, then the competitor next door who sells the same items - but doesn't charge 3-4% for non credit card transactions - is, all else being equal, more attractive to those customers. I guess whether or not that counts as a big issue would depend on the customer. Personally, especially for items that I'm routinely purchasing over and over, I tend to notice where prices are higher or lower... I don't bother calculating how much higher or lower, I just choose lower (again, all else being equal).