If that's allowed under the credit card processing merchant agreements it's a new development. If I had to guess, it's still forbidden, but small shops don't k

If that's allowed under the credit card processing merchant agreements it's a new development. If I had to guess, it's still forbidden, but small shops don't know/care until the CC company actually asks them to stop. If people could get a 5% discount everywhere with their debit card, the gig would be up, and the CC companies know it.