I'm always "scared" of retrospective falsification because it is a form of bias and I always try to be as objective as I can. So when I recall a story such as your rude waiter example, I try to admit -firstly to myself- my own mistakes and how I might have contributed to the outcome of the story. This exercise has personally helped me have a more accurate memory in events involving other people because I try not to let emotions distort memories, whether they are good or bad memories.