Ihunt, sure, its pretty easy to explain.
Outdoor recreation generates 887 billion in consumer spending, that supports 7.6 million American jobs. Much of the outdoor recreation we all enjoy, along with the economy of same, is tied to Federal public lands. Along with that comes billions in taxes paid to local, state, and the federal governments.
Depending on the sources you find, the estimated cost to the taxpayer is about 8-9 billion a year to manage federal lands.
I'm unsure on how that cost of management is off set by grazing fees, mineral royalties, timber receipts, etc. etc.
Don't forget to, that there are lots of benefits that people receive from Federal lands:
What is clean water worth?
How much do States benefit from the BLM, NPS, USFWS, and FS providing wildlife habitat, food, and water for the States wildlife Resources?
Also, keep in mind that under multiple use management, there is NO mandate for federal lands to make money...none. That's for good reason, since it would be impossible to manage in a way "that some land be used for less than all of the resources, and harmonious and coordinated management of the various resources, each with the other, without impairment to the productivity of the land, with consideration being given to the relative values of the various resources, and not necessarily the combination of uses that will give the greatest dollar return, or the greatest unit output".
There is a huge misunderstanding, mostly pushed by politicians that haven't the first g-damn clue about what multiple use really means, that we have to squeeze every last dollar out of our public land resources. Its a complete and total lie, and the most basic lack of understanding of what the MUSYA says and what multiple use really is.
I would contend that either our politicians have a complete lack of comprehension, have never read the MUSYA, or are a pack of lying, bought and paid for bastards, when it comes to the concept of multiple use. Frankly, I don't care which of the 3 it is, but they better get with the program, because myself and many others HAVE read the act, know what it says, and what it means.
But, all that aside, there is very little question of the value provided to the economics of the United States from Federal lands, not many things I can think of with the same ROI that our public land assets provide.
So, yeah, they pay for themselves many times over.