The goal of such recommendations is not to ensure people can survive 72 hours without access to additional supplies, but to ensure that the society as a whole can function at such a situation - that requires a lot more than just a drop of water and barely enough calories to stay alive. If the enemy can collapse your society just by destroying a couple of power plants and water treatment facilities, you've already lost the war. Or climate change, or blizzard or what ever it is you are facing.
That being said, I do agree that the food you store doesn't need to be anything special or tasty - just something to keep you working your job and taking care of those that depend on you.
Dredge was such a treat on Deck. In addition to being just a good experience overall, it seems to strike a perfect balance in several ways to be ideal on the deck.
Like it's not that demanding so it runs very smoothly, but it is still beautyful and takes advantage of the extra power available compared to other handhelds. It also has a simple and short main game loop making it easy to pick up and drop, but also an interesting overarching plot to draw you back into it over and over.
I wish I could find more games like IT to play on the Deck.