Exactly. Do I find it annoying? No, but if I interacted with children much I probably would. Kids are annoying, but stuff like this is culturally valuable because it's them practicing growing and changing culture. Things that annoy the old people like us are also part of how teenagers get us to leave them alone so they can grow up in peace. From there younger and younger kids copy older kids because that's how kids work. Then eventually the parents and teachers that understand kids will get in on it poorly when they're well and truly sick of it.

Hell, every once in a while the kids get into something good, though it's usually music or books.