Serious raiding guilds already do this, I ask for mats and people put them in the guild bank then I craft potions, flasks, and food for raids. When the Warfront donations are up, people just put the turn in items into the guild bank for anyone to take and get their stuff. We have a tab for crafting mats, if anyone has a mass surplus they don’t need it usually goes in there for anyone else to take. Another guild tab is for enchants, glyphs, and gems. Even got a tab for pets, mounts, and toys that all free to take for anyone; most tend to put in their extras.