>> storing that excess water isn't free. Water is already commoditized, which means it's low-margin. If you as a private business, stockpile water for an emerge

>> storing that excess water isn't free. Water is already commoditized, which means it's low-margin. If you as a private business, stockpile water for an emergency but can't charge more, you're probably selling at a loss. > During a disaster they can keep selling at $X/bottle and keep making a profit You ignored the point of the person you're replying to. This applies to the entire supply chain, too. If there's any disruption (including increased demand), it's the stockpiles -- anyone that stores inventory beyond what they sell regularly -- that compensate. No one is obligated to do this, and there are significant carrying costs to store inventory (space, spoilage, capital tied up).