The argument doesn't hold - if cards were only about getting sales which they otherwise wouldn't get - and the part about "getting sales which they otherwise wouldn't get", is true enough - then there's no reason to refuse cash payments. That's additional sales, right? But the fact is that more and more shops refuse cash payments entirely. "Pay by card or go somewhere else".

I can't comment on this fact of more and more shops refusing for cash payments entirely as I personally have NEVER seen that?

Provide me an article or some proof to this fact for me to comment further as currently we are at an disagreement on this thing which I hope we can turn into meaningful discussion.