If going home with 20 extra bucks or leaving behind 20 extra bucks makes you feel victorious, then enjoy!
Me, I have a set chart in my head of exactly what I will tip for what thing that might happen. I have the HF pile, the basic tip pile, then the extra, third pile. The HF of course goes out right away, the tip pile sits on the table under my glasses for her to look at and touch and do whatever she likes with, so she might know before she even touches her oil bottle exactly what I intend to give her. But only a few know about the third pile, which stays in my pocket. It's there, it's waiting, it's hoping that something will happen to prompt me to touch this pile and split some of it up and give it to her.
But either way, I get what I am there for, and the lady, she gets what she's there for. And you, well, you get the story, and you get to know how much was in the first pile and the second pile, but the third pile, what happens to that pile is between me and her. I feel like coming home with money in that third pile means my hopes were too high in the initial part of that morning, and it's not likely I would like to go back to that place again. Some, cheap bastards like my father, they enjoy to come home with money, because they are cheap bastards, and money means more to them than anything in the universe, even their own pleasure. Of course, while I get BBJ at Hand and Stone, lady typing her cell phone number into my phone, he and his pals get a jackhammer from an old bag at Absecon, who stares at the ceiling hoping it will end soon.
Enjoy the universe, it enjoys whether you do or not!