Just stayed in loop 1900 and we used the site's grill every day. We have a small proprane one, but we prefer to use Disney's why not it's included with the site's rate.
These are still the older charcoal grills in this area, so you'll need to watch the weather when grilling out. A light sprinkle won't bother the food cooking as their are so many tree's to help block out the rain. Course you could laso just cover the food on the grill with reynolds wrap too until it lets up. But, I'd say just watch for storms.
These are the full hooks in the 1800-1900 loops so they don't have the newest stuff.
The premium sites like the loop 800 (where I have also stayed) have the new grills and they have a metal cover that lifts up and down that will keep the rain off your food as well as a larger octagon nicer picnic table. But the one we had in 1900 was clean and well maintained.
Hope this helps...