The way (most) restaurants work: Your waiter will be paying out 3-5% of their gross sales in bar tip-out, hostesses, busboys, etc.. When you fuck your waiter by not tipping or tipping a lower percentage on an expensive meal, you are costing them money for the privilege of having waited on you. Fuck you very much, die slow, etc.. They also pay that on liquor/wine sales, so do not exclude those. At the end of the night, the waiter must claim all of their credit card tips and are strongly encouraged to claim 10% of their cash sales so both sides can avoid any troubles with the IRS. It's been a while since I had to go through the process, I can't remember whether or not that was 10% of gross after tip-out or before. And no, the restaurant will not let you claim no tips - in that case, they would be liable to make up the difference in your tipped-employee wage ($2.13 in most states) and whatever the state minimum wage is.