You are I assume talking about Supply? Look, I would absolutely love to use a more realistic method to handle survival, with food and water being separately tracked and handled realistically. But it is nigh impossible to get players to buy into something which is functionally a straight negative from their point of view, no matter how much I like it or would be fine with as a player myself. So I accept Supply as a necessary abstraction so I can actually have exploration and travel rules at all.
Just like hit points and the combat rules.