I myself have worked at Speedway, the midnight shift. It would have been unacceptable for me to lock the doors for a half hour (or longer). Not to mention the restroom is visible from the front door, the girl eventually stumbled out of the back somewhere looking half asleep.
It's possible if the csr is having an upset stomach this store in particular tends to be short on hours so if there's only one person on deck it's very possible.
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