Measure of a man

I've been working really hard at turning myself into a good man. They say that a good measure of a man is whether he holds on to his core set of morals and values in the most pressing situations.
In this respect, I failed yesterday.
I am a waiter at Mac Shack. Every day we have people (Bussers, food-runners, bartenders) that help us out with everything, they get a better salary than us but we usually make more money with our tips. At the end of the day we compensate them by tipping out.
Yesterday, I had a very small situation get out of control and I let go of my beliefs.
Here's the story.
I had a customer leave me a nice tip but unfortunately he took the receipt that was signed and left me his copy. I can't claim that copy. I even asked my manager if I could. He rejected me, and at the end of the night I took it out on the people that helped me by not tipping out.
It hit me much later on in the day that my helpers had nothing to do with the problem. It began to eat away at me. I had problems driving and holding a conversation. I was ashamed of what I had done.
I went back to work as soon as I could and told a manager what had happened and begged him to let me tip out without anyone knowing. He agreed.
It was very embarrassing, and I hope that in the future I can uphold my integrity in pressing situations.