Now if you can deliver this in a plastic free or reusable packaging this would be a winner!
Perhaps point of sale refilling stations could work? I imagine a modern take of a gum machine with a video screen showing the benefits of the product. Branded, scannable reusable containers can help you track consumptin patterns and link consumers with rewards.
This would provide a big marketing presence in store and allow consumers to refill your containers for rewards or use their own container. POS refilling would also minimise your freight costs as you would ship in bulk to retailers.