I think the key difference between this and the wall on Beach 2 is that this is relatively difficult to get to, especially for more than 1 person. The wall room on Beach 2 takes absolutely no skill, and one human can let half his team in there to protect them from zombies. AND they can get kills while in there, or even break legitimate cades in areas that are adjacent to the wall, which runs along the entire above-ground beach building. I personally witnessed a ton of cade breaking happen during the time that the wall room was legal, and it's very difficult for admins to monitor and punish that without being in spec, since you can't even see who is back there otherwise.