Definition: Given a real-life anecdote of a complex ethical situation, generate a suitable title that describes the main event/root cause of the situation. Imagine that the given text is a social media post, and you have to write the title of the post, so the users can decide to read the main text or not.
Input: I was at the pub and I ordered 2 pounds of wings and a 7up.  Over the course of the night, I should note that, the person waiting our table changed twice.  One took our order, another brought our food, and a third took care of us for the rest of the night.

There were 7 of us and 4 of us got our bills while the other three stayed behind.  Well this waitress brought my bill and it only had one pound of wings on it.  No 7up, no second pound.  I was delighted that I only had to pay for the one pound.  Then she realized that she left the 7up off of it and added it on.  I paid and tipped 15%.

When we were about to leave she came back and asked "Did someone have 2 pounds of wings?"  I sat there hoping not to be found out but all of my friends ratted on me.  So I said "Yeah I had the second pound. What do you want to do about it?"

She brought me the bill and I paid on card and this time I tipped 0.

Am I the asshole for FIRST not pointing out the error on my  bill and THEN not tipping when I paid the rest?

TL;DR waitress forgot the second pound of wings on my bill and when she realized and I had to pay, I didn't tip.  AITA?

not tipping when the waitress made me pay for an item she left off my bill