Oh the kids I've spoken to know what they are doing too. They do not like having it pointed out by an adult.
That the adults didn't do anything for you or acted like they couldn't is a failure on their part.
Kids will be mean on purpose because it can feel grown up and powerful. They see it in media, or they know an adult like that. They don't always think about the fallout fully.
But when another adult isn't impressed it's not so mature and worldly seeming anymore.