I guess. But either is fine with me. Credit cards have leverage over small businesses who often have tight margins. As for up-charging tourists who visit places in foreign countries, I think of it as a subsidy. If they normalized the entrance fees so that all paid the same, and the total maintenance costs were met-- this may well 'price out' poorer locals. A nicer solution might be income-based, but how would you verify such information at a park entrance?

I also want to add that where I live in California, there are some local attractions that offer discounts to local residents. I really can't understand the fuss.