[thaumasiotes]

> Didn't the ending heavily imply that the theme park was just a trick of LeChuck?

Yes. As they walk out into the theme park, LeChuck looks at the camera and his eyes glow.

I think this is just another entry in the genre of "there was no plan, so the writers added several different plot hooks on spec".

[Trasmatta]

Also, during the credits, doesn't the game switch back to Elaine who says something like "I sure hope LeChuck didn't cast a spell on Guybrush"?