It's a mandatory tip so we view it just like the restaurant that adds a mandatory 20% on a party of 6 or more. We'll pay it but we're not going to pay an additi

It's a mandatory tip so we view it just like the restaurant that adds a mandatory 20% on a party of 6 or more. We'll pay it but we're not going to pay an additional tip. 20% (or 18% if you think it's not going to the wait/kitchen staff) is rather generous so please...