A Short Rest is a period of downtime, at least 1 hour long, during which a character does nothing more strenuous than eating, drinking, reading, and tending to wounds.
It is implied that eating and drinking are involves to regain health. In the words of Nacho Libre, "It gives you nutrients, and some strength."
Going all day without food and drink wears a person down, especially if doing strenuous activity. It makes sense to require it, but again, ONLY if easy to manage. Micromanaging MORE inventory would not be fun in current state. Still, would make splitting camp supplies between personal inventory and camp more meaningful and strategic and immersive.
