It's not the feds being greedy. The idea in 42 US Code is that the federal lands are public lands, and the federal government has a responsibility to fairly use those lands as long as they administer them. In this case the law says the Feds must not favor someone with a no-cost lease, though this is an obvious oversight in the manner in which the law was written. That said, this oversight is a pretty special case considering the use of it as a park and it's APZ-1 designation.