The restaurant forged a higher price, plain and simple. Call the CC and challenge the charge.

Re tipping in the US, your perceptions are right.

Now stand back and watch about 20 posters say that the entire concept of tipping is "outragous" (mostly folks who live in countries where tipping is not customary, as well as a few uberconservative Americans) while a few posters will defend the practice.

It seems we have to go through this every few months.