Regarding your comment "the jeans that no longer have knees"
I believe that unwearable denim clothing items are not able to be used by op shops in general as they are for some reason regarded as unsuitable material for cleaning rags.
I have been trying to find a place to recycle/reuse my torn denim jeans and keep being told if I donate them to an OP shop they will just end up in landfill at the OP shops expense is all

That's a really great point Jonat. I wonder whether crafting groups might be interested in the denim, as they can often be repurposed into great projects. It's a lot harder to find groups like that though.