It's been a while (~10 years) since I've had to deal with credit processing, but at least back then, discovers terms were pretty abusive for small businesses. I

It's been a while (~10 years) since I've had to deal with credit processing, but at least back then, discovers terms were pretty abusive for small businesses. In any month where we processed 1 or more discover transactions we had to pay a minimum fee of (iirc) $50. Given how relatively unpopular discover is the risk was just too high.