I guess I should add that, specific to campgrounds in National Parks and other government land, the original (now called liberal) idea is that their existence benefits everyone, not just the specific people who camp in a specific campground in a specific year. So the cost (originally all of the cost, now part of the cost) is spread out over everyone.
I personally disagree with the move to change everything to user fees ('lower taxes') and make users pay for 100% of the costs of maintaining the parks and forests and everything else. I think it makes camping unaffordable for a lot of people who would like to go. It turns camping into an elitist activity and I don't like that.