Yep, I might also write that down on the check so the waiter can relay my dissatisfaction to the owner/manager as well as gripe about getting less in tips.
If I had to pay cash for meals, I would eat out less due to the inconvenience of having to keep enough cash on hand.
I also would tip less. If I wanted to leave a 10 dollar tip, yet I only had twenties and a 5 dollar bill in my wallet - guess what I would leave?
Restaurants should thank God for customers using credit cards.