@Eric Albus example of a fence is a weak one, I think he would agree, that a water pipe line is a much better example. Most pipe lines originate on private because water resources are often limited on public. There is wildlife on public land that simply would not be there if not for some of these pipelines.
Pittman Robertson taxes is also a weak augment, You are asking the private land hunter in Texas to subsidize your public land hunting. A user fee would be much more fair, but I am not in favor of that just yet for recreation, but I could get there.