The incredibly convenient, lifesaving tables that show weapons/apparel and their "Smelting profitability cutoff" has a couple flaws. The table shows that some Apparel items, like Tox Packs and Firefoam Pop Packs, have differences in quality (awful, normal, masterwork, etc). Those items don't have qualities. So there should be only one y-value (smelting profitability cutoff.)
I play on 1.5, so if this is something that got changed in 1.6, forget about this message.