Stamina cost can be reduced at any time but crafting items like bag, pouch, sack, etc needed time to code and was not an independent task. A lot of dependencies like recipe, drop rates, storage, resource encounter rate, luck factor, etc were involved. We will be sharing the details of each and everything as we continue to post about Beta Release.
Beta is not going to be like alpha where there was not much to do anyways. Hope you'll come back and enjoy the feature loaded game when beta launches. Till then you can enjoy MOLE MINER if you like such games.