Our proteins and supplements are sold by weight and not by the amount of space they take up ie volume.
Some proteins are denser than others. For example our Naked Pea is much denser than our whey protein, and this leads to a less than completely full canister. The products are weighted multiple times to ensure it is the correct size. If we filled canisters all the way, some proteins would weight out to 8 or 9 lbs, with a price increase to match.