I've had it happen on numerous trips to cruises, which would be expected, same people going in either the day of the trip or the day before, and everybody leaving the same day to get back home.

I flew out to Chicago way back when to reboot a file server (and put in a remote reboot device so I would never have to do that again) and not only was the same person on the plane, he sat right next to me again.

A destination wedding was one time, but that shouldn't count, that was planned.