The point of those systems was to limit damage from vibration and rocket exhaust on a normal launch, not to allow the pad to withstand an explosion. (And SpaceX does have them as well; the pad deluge system is more visible than usual in this video of the Dragon pad-abort test, which was conducted at the same launch pad they use for Falcon 9s, though without the rocket itself or any of its mobile support equipment: https://www.youtube.com/watch?v=1_FXVjf46T8 -- the large streams of water kick in a few seconds before the Dragon abort thrusters kick off.)