Believe it or not, we actually have had to ban people before in the past for such thing; one guy in particular had a habit of responding, "Yeah, I agree" ALL THE TIME. Likewise, he was asked repeated to be mindful of discussions, as well as put a stop to posting, "Yeah I agree" over and over and over again on almost every discussion that was going on. He got better for a little while, but then he started up again, was asked again to stop with the, "Yeah I agree", but he continued to do so, and eventually was suspended. And he was an adult, actually.Other forums, like others have said, would haver BANNED you for such nonsense.
Personally, I think expecting young members, even teenagers to act like adults on the forum is going just a little too far (I've been a moderator on a forum once where we had a couple of 11 and 12-year-olds who really didn't misbehave at all, though one of the admins begrudged them simply for being kids and and tried to make them act like adults or leave the forum... and that was a forum for Alvin and The Chipmunks, so it's a similar situation like with the Muppets, you have to expect members of all ages to be a part of the forum), however, I do agree a little maturity is in order here. To repeatedly ignore people asking you to reevaluate your behavior, then to call people mean, unfair haters when finally calling you out on it is rather uncalled for, do you mouth off at your parents when they have to discipline you once in a while?