I don't know why you were downvoted, I came to write the same idea. The brewer paid for the energy required to clean the saline of unwanted energy, and the sho

I don't know why you were downvoted, I came to write the same idea. The brewer paid for the energy required to clean the saline of unwanted energy, and the shop owner pollutes the saline by adding unwanted energy back into it, incurring an additional cost for the brewer as he must expend more energy to also remove the energy added by the shop owner.