Cleanup shouldn't keep you from the fire. Five minutes while the griddle is still warm and you're done — and ready for breakfast tomorrow.
The routine is the same every time: scrape the food debris while it's warm, add a splash of water to loosen what's stuck, scrape again, wipe it dry, and apply a thin coat of oil. That last step is what keeps the surface seasoned and rust-free.
Two things to never do: leave standing water on the surface, and pack the griddle away wet. Let it cool fully before it goes in the vehicle, and store your spatulas and scraper somewhere dry.
A griddle that gets a quick wipe-down after every cook is one you'll never have to restore. Take care of it on the trip, and it's ready for the next one before you've even left the campground.