Does the park charge different rates based on race?
Here in Thailand you can place or search for caches in national parks, but if you're white, black, hispanic, or even Japanese or Korean you'll be paying a lot more than you think.
Thai nationals = 20 Baht (57 cents)
Foreigners = 400 Baht ($11.42)
Foreigners married to Thai nationals = 400 Baht
Foreigners married to Thai nationals with children = 400 baht
Sounds to me like a standard $5 fee to enter a park is quite nice and reasonable. Especially when that money actually goes to park improvement, etc. instead of into someones pocket like here in the Land of Smiles. Based on what they are charging here in Thailand the entrance fees in America should be much higher to account for higher costs, salaries, etc. accrued by the forestry departments.
Living and working in another country for over 5 years has given me a true appreciation of the freedoms most western countries provide and the parks we can enjoy.
Aloha