This year I had the opportunity to visit three of our national parks. The first observation one could easily conclude is that the vast majority of visitors are foreigners. They arrive by the busloads evidently from an aggressive promotion by foreign travel agencies. Why not treat these visitors much like we do non-resident students at our public universities? Instituting a pricing structure that benefits the American citizen seems a fair solution to the ever-increasing maintenance needs.
Also, establishing a mandatory online ticket purchase with gate scanners would ease personnel burdens, long lines at entrance gates, and accurate accounting of a visitors origin.