There should be the ability to "lock" an item, for those of us who are paranoid about donating or selling something we don't intend to by accident (this has happened to me; thankfully it was just a hatchet, so I easily bought another, but it happened due to my computer lagging and it was so fast that I didn't even see what I'd lost until I checked my tools). Maybe there could also be a way to lock an entire bag, so that everything in it was safe. We'd still be able to use the items, like if you're collecting music blocks, you'd still be able to play it, but it wouldn't show up in the donate box and any attempt to drag it to a vendor or shrine or other person would fail.