"A separate day-use fee may be required for users who park at the Grande Ronde Lake Day-use site near the lake."
That usually happens when a sub-contractor has "taken over" management of a specific area - and that sub-contractor decides it's LESS PROFITABLE if it allows campers - who already paid for a site - access and then charges a fee for an area that was developed with OUR TAX money.
In our experience, most often when a private contractor takes over something like this, service level goes down, trash lays around longer, the restrooms need servicing, and we pay an additional fee to enjoy it.