I-77, Exit 36, Mooresville,NC has a Cracker Barrel on the west side of the exit with RV parking spots and there is a Wal-Mart on the east side of that exit and south of the cross highway.
I have stopped in both over the years when making our many flying trips from PA to somewhere in the south. Usually just a few hours of sleep and back on the road, but try to use the restaurant or the store for meals or supplies.
Leaving this exit and heading further south is better if you do so early before the commuter traffic picks up so you can buzz right through Charlotte.