I don't think it's being themed to look like a spaceship, just a more finished version of the building that's already there. The form matches the front treatment. All I'm saying is it will be guest viewable- from where and why I don't know.
The only other thing I can think of is if the shuttle has a window on the top that would open up in atmosphere. Looking up we would see the natural Florida sky and as our craft enters the structure we would see the building which is why they would need to theme that section. The artwork for the shuttle that takes us up to the Halcyon from earth actually shows such a window, but I don't believe the one that takes us to Batuu includes this (they are very different craft actually.)
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