Here is something that I think works for me and it can too for any waiter out there. No matter what always show gratitude to the guest.
They could have ate somewhere else.
That is not to say they could have tipped more but maybe they don’t usually leave a tip.
One thing I believe in is if you set up good karma no matter what happens by the end of the night you will come out ahead. Be focused on the end result and that is when you count your cash at the end of the night. Not before.
Just keep your wits about you and serve serve serve…