How is the game going to determine what is "junk" to you that you want sold versus what is valuable that you want to keep?

Most items in the game have a purpose beyond being sold to a vendor for gil. The Salvaged Accessories, Clear Demimateria and Allagan Pieces are the rare exception (along with probably a few others I can't think of off the top of my head). But even those some players would want to keep separate to use at Doman Enclave.

Without something that automatically differentiates the two, the wrong items might get sold while the right items are ignored.