Because he is already maxed out. Unless they have certain items that he needs. He won't pick up extra items. Even though all of my items that I need to throw or set may not be full, you need certain items to make it. If you have enough items like rags, it won't just save any extra. You're going to have to use them to make the items. So it really is a good idea once you go search over the body to make sure you can't make an item.
