Could she be a hoarder?
Yes, that is our Hiker. She did something similar when she was first adopted. Back then, Hiker would pick up mittens, shoes and slippers and put them in a pile. She has started again and now takes everything into her crate. There is never any damage to anything and she has no problem with the items being taken away and put back where they belong.
It becomes a game where I will follow her, lightly stomp my feet and demand to know, "where are my slippers?!" Hiker gets excited and we play a soft game of tug until she gives up and rolls over for a tummy rub.
Well, hoarder or not, we love her and her slightly odd behaviour. Besides, its always easy to find the slippers and mittens that may go missing.