Oh I hate people like that! I usually roll my eyes or correct them. They don't usually like being corrected, and probably still think they're right.
I don't have a parent comment, but I do have an adult to bus driver comment. This couple gets on the bus on the back stairs (where it clearly says "Do Not Enter". I guess the bus driver closed the doors, either not seeing the people or thinking they were far away enough from the door that it wouldn't hit them. Well, at the next stop, the woman goes up to the bus driver and says "don't you EVER do that to me again!" and the bus driver is rather puzzled, so this woman's husband comes up and explains what happens and the bus driver says he's sorry but that you aren't allowed to enter the back door to begin with. The woman is still furious and leaves the bus. There are a few bus drivers milling about outside (Pleasure Island stop) and he says to one of them "hey, did we takes those "do not enter" signs off the back doors?" and the other one says "yeah, we put them on the front". Haha! Can you believe that woman? "Don't you EVER do that to me again!" What kind of a comment is that? What is the likelihood of ever seeing that bus driver again? And that just isn't the appropriate comment for that situation, if she was going to have to complain. Yeesh.