How much would it really cost to stick an already-existing sword graphic onto the body, though? Or say, the graphic for how an armor looks on the ground to the body as well? Granted, there are more nuiances to body animations, but I think if it could be done, it should be.
Though I'm not an artist, I'd say that it would cost alot more. Go use an item and look at all of the individual frames of animation that are involved in using that item, (just look at how your character changes with and without the item). Realize that the game doesn't use a 3d engine, so to my knowledge, every item that you see would have to have every necessary frame of animation drawn for it, you can't just stick it on. You can certainly take a template and add one piece of art over the other I think, (so you wouldn't need to redraw all of the armor, etc.), but my guess is still that it'd be alot more work.