Auction House - "Rarity Sorter" may not work (unsure if it serves any purpose)

In the auctions menu, if you hover over the enderpearl, there is a "Rarity Sorter" with options of Common, Uncommon, Rare, Epic, and Legendary. Setting it to any of these options shows no items, so I'm not sure if this works (in fact I don't know if it's meant to be here to begin with) It's possible this was for Factions and ended up on RPG somehow? (as Factions has items with these "tiers" but I don't think RPG does)