I believe it was the $30 - $60 a day per rider that encouraged that. And I don't know why it would be attractive as a development when it's surrounded by 1000's of other undeveloped acres in the middle of nowhere.
Towne Lake started a similar way, so did every other town and development.
Also, as iron clad as any "waiver" maybe, if the land owners or their associates knowing allow unclaimed risk, then the waiver won't stop or help.