Watching Shore Leave right now. I know at the end of the episode the caretaker explains the purpose of the planet. It struck me that it seems like whoever created the amusement park has great power. Not only can they read the minds of the visitors, they can create lifelike versions of people and things. Think about the briefing room scene in The Cage/Menagerie when discussing the Talosians powers. If in the wrong hands, would this ability prove to be more dangerous (or equally) than the Talosians? Visit Talos 4, get the death penalty. Visit this place and have a cool vacation. Should Starfleet be concerned about this place?
Imagine the data Disneyworld would be selling if they had the Caretaker's little silver antenna.