We went to a nice expensive place in a California mountain resort, big bill and nice tip too for the pleasant service, all on my credit card.
When I got home they had had a second take of a further $100 from my credit card some days after the initial transaction.
Before I got round to calling them got a very abrupt letter from "accounting and audit" which just said "Wrongly charged - extra $100". Photocopy of bill enclosed where auditor had written on it various corrections and then CROSSED OUT and subtracted the tip with "No tip - incorrectly billed !!" written alongside.
So they had taken every extra penny themselves they were in arrears and then taken all the tip away from the waiter. Where was the Maitre d' checking the bills (isn't that their job ?) Not nice.