Now that I think back more carefully, even 25 yrs ago we did leave via the ferries, and our busses were at the MK lot in designated spaces, where the offsite resort shuttle busses normally pull in. We were not allowed to leave before sunup, though, and we had to meet at a designated spot in the park and walk out in a group with everyone accounted for, so I guess the exit procedure has changed a bit over the years.
Please forgive me if I got some of the procedural details wrong, it's a wonder I can now remember any details at all