And I bet his guests drove on public roads to get there. Some of them may have even have had public educations!

Taking advantage of government services available to everyone does not preclude one from expecting the usual degree of privacy and respect we accord to our fellow citizens.

It was private land, according to this article.

I think it was actually private land, which was simply made accessible to the public under certain conditions. Parker's position is that the campground was temporarily closed anyway, and that his wedding did not deny anybody access who would otherwise have had it.