To be honest, both NvS and Mayhem were down on numbers this year, Paintfest probably too, there does seem to be a general decline in attendance year on year since the peak.
However, I remember speaking to a tournament player who's first Big Game/Scenario experience was the Zombie land debacle at the theme park. That experience put him off all such formats for the future, I wonder how many other players have come to similar decisions.
On an aside, I heard that the park owners weren't initially told that Zombieland was a paintball event.