I've spent the night in a 5th wheel many times without problems. Just don't park too close to the actual store.
Why don't you just go to a hotel it's much more comfortable
I'm pretty sure they won't encourage it if you call them but do it anyway. A few people have done it. You might be lucky and get a sympathetic manager. Or better yet, go into the store and ask someone. Who knows.
You may want to give them a call. I'm not sure about cars but I'm pretty sure I've seen semi's parked here overnight.
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