Not strange at all, very cool. I love when they dispaly the clothing and sets, because you can tell which is fake and not. The process of aging the clothes for a costume takes a certain number of techniques. Also....
I am Absolutely sure that the clothes on display can be that of one of numerous copies. For each character they have doubles, stand in's ect..each having at times the Same copy.
SO It might have been worn by rupert, dan or emma or by their numerous doubles. each character can have 6+ copies of one costume.= lots of work.
Really nice pics by the way.