The article quoted states:
Basically, by limiting what card payment companies are allowed to charge retailers per transactions, some rewards cards may have their futures cast in to doubt.
Raffles posted an article on this recently:
http://www.headforpoints.com/2017/07...-for-the-card/
We are talking about two different things here:
- merchant charging customers when using credit cards (article posted a few posts above)
- issuers charging merchants interchange fees (your point)