She didn't apologise because she got given "the look". Perhaps she would have done otherwise, who knows. Perhaps she wouldn't have and she's a yobbo, we don't know.
The thing is, if you look down on someone who has screwed up, you don't give them a chance to apologise and make amends - you change the dynamics of a situation, which is exactly what happened here - I don't see how the passive aggressive look and shake helped there, it irritated the OP and she stropped off. That may be unreasonable of her, but I honestly don't think this way of treating people is conducive to co-operative behaviour and I don't know why people are arguing that it's a Good Thing. It's a horrible way for us all to be acting.