Hey they didn't specifically mention ninja suits as "unacceptable"!
Nor pirate costumes!
There no condemnation of togas as far as I can tell either.
I'd love to see a group enter with someone carrying that brochure, and arguing with the receptionist, "show me where in the brochure it says we can't tour Bethel while dressed in our lederhosen".
I've said it before, and I'll say it again: