The Magic Kingdom itself apparently sits on the 'third floor' of the resort. Years ago, a character from Frontierland was spotted in Tomorrowland, as he was shift changing. That was apparently unacceptable, so a labyrinth of underground areas were built to shuffle park employees from one side of the park to the other without being seen by the guests.
They also own their own power plant and control water sources. For many years, abduction was a rather common occurrence.
Also, I cannot recall seeing one landscaper during the day time on any hotel or park property - and yet each shrub, lawn and tree was manicured perfectly.