Getting 4,000 mL of clean water in a jug makes you immune to dying of thirst for several real life days and is incredibly easy to do right from spawning in on the coastline.
Getting an entire inventory full of food is also laughably easy. Fishing, blueberries, bear meat, food crates in general will give tons of food in no time.
As it stands right now, you could remove hunger and thirst and it would change nothing due to how trivial they are. I think the decay rate for food/water could be doubled, or even tripled to add some extra spice to the game. It is a wasteland out there, after all....