I wish it was that simple. Insurance is a lot more complicated than you think. For parking lot events you need a lot of protection for the drivers and spectators, especially the spectators, because nothing covers them from a car spinning out of control coming their way.
Buying property isnt too cheap either, and paving it properly is probably just as costful.
I mean, I would love to see it happen, but right now it's a lot better to just drive to orlando for events. You say you practice for "a few hours" but you have no idea how rewarding that can be if you put that time to good use. It's most definetly a worthy experience and you should try it yourself.