Yeah some friends thought the same (as did I) until I "stumbled" across the reason behind the Speaker not having materials for exchange. I'd love to know the reason the speaker is breaking tradition from all the other vendors. It's puzzling and very annoying to have to carry/load up on materials just to see what is available when all other vendors simply show you what they possibly have for sale/exchange. It would be nice to change this behavior for the Speaker as it's confusing at least, and frustrating as best :( pretty please Bungie?