The main campground has grass. Last year, the backstage campground had wood chips (maybe that was what you thought was gravel?) It used to have grass, but the wood chips were the result of damage from teh flood of 2013. It might have grass this year, maybe someone who was at Rockygrass, or one of the staff could clarify?
One the main campground you can have a vehicle, if you buy a vehicle pass. Backstage you can't have a vehicle.
The previous response covered the two off-site campgrounds. (They're walking distance)
There is a bathroom with showers and hot water. Not just port-a-potties. Very nice for a festival.
There are food vendors with good food. You can walk 1/4 mile to the grocery in town for lunch meat, bread, fruit, ice, etc. And there's a liquor store in town. You owe me a beer for answering this.
It can get a little cool in the evenings, during the song circles, so bring a fleece jacket or hoodie or something.
Hope that helps! You'll love it!
Listening to:
my own music, actually. I'm recording a new album.