I always have my motorhome backed far enough to put my toad (truck) in front. I have never had any problem with my rear motorhome tires sinking more than a couple of inches into the shell/gravel bed and my leveling jacks have a big enough pad that they don't settle deeper later. I have had to stick the rear of my motorhome into the bushes to squeeze everything in.
The biggest problem I have had (more than once) is because of where I like to stay (site 116), which is right next to the path from the 100 loop to the Settlement / Landing area. I have driven to other parks before, come back to my site and found that someone has had the nerve to park in my campsite in front of my rv, taking my toad's spot, to go shoping, eat at Trail's End or whatever. Normally they show up within 30 minutes or so in time for me to give them a good tongue lashing, but once I had to have one towed by Disney. When the occupants showed up later that night after MK closed. They banged on my door & became irrate with me, I called security and they, along with the Sheriff's Department came up. The guest, and his wife, continued to show their rear end. They were escorted to their cabin, made to pack, and were put off the property. Their big excuse was 'there was no sign saying they could not park there'. Well, in the immortal words of Ron White, "You can't fix stupid".