Good to know, I wouldn't have thought about it and people have mentioned bringing them to keep kids entertained. My son is 4, and his five cousins who are coming along are all close in age and would love them. I'd think twice about it now.
Many people on the boards here have mentioned not climbing on the railings which, unfortunately, I know my son will want to do constantly. He's a climber and a jumper and a mover. I'm just hoping he'll do enough jumping and walking by the time we get to the lines that he's going to be less inclined to climb. I doubt it tho.