I was your server, and did not mention that it costs more to add fresh shrimp to a salad only because it seems obvious. If you wanted to know the cost, just ask.
People do it all the time.
Also it was very clearly stated that tip was included for parties of 5 or more on the menu and the check. Beings the 5 of you had calculators and the check for at least 30 minutes, I assumed you noticed. As you did not, I only accepted the included grat and voided the added tip that you left. You knew this because you talked to our owner the next day. I called them during the day more then once trying to arrange a dinner for family event.