In college, there was a tutor who came to the common area of the dorm every Monday afternoon for 2 hours. Someone saw him walk over from the dorm across the street, so they assumed he lived there. (The guy was probably in his late 20s or early 30s.) When we pointed out that he probably tutored there, too, the story morphed to someone had SEEN him come out of a dorm room!
Finally someone asked about it. Apparently he lived off-campus with no car, so he worked out a deal to crash in an empty room on the nights of tutoring. Most of the time, he took the bus and went home, but for whatever reason, he didn't do that every night.