Comment by lxgr

Even as somebody really disliking the current interchange fees in the US, 4% is a money grab on the merchant's side that I find hard to empathize with.

Even if the merchant pays the sticker price for card acceptance, it's usually just below 3%, unless international cards are involved. Add to that the fact that cash transactions in restaurants are often accounted for in "more tax efficient ways", and it feels even more icky.