There is some logic to the madness. The cave would be a good place to camp yes, but because of the spawn being right next to it, it would get a constant stream of fasties, as well as waves of "ground-locked" zombies from the moving platforms. Small means constant action, no waiting because the zombies have to run a marathon to get to the humans. The movement issues, as well as the ever-present danger of falling down serves as a counter-weight to the camp-spots. Still have no idea how the actual map plays, it needs playtesting