I've stayed in many Cracker Barrels. They are one of our favorite overnight stops. We usually have dinner and breakfast there.
CB closes at 10 S-T and 11 F-S. Thus all one has to do is arrive 8PM or later and you have plenty of room to park. I usually park on the side across 6 or 7 car spots. My MH is 39' long. I rarely park in an RV spot. We try and leave around 8AM after having breakfast in the CB. Once during breakfast I mentioned to the manager that we spent the night in his parking lot. The manager picked up our breakfast check.