It already is: if the game is too difficult for you with Hunger, then change the difficulty.
Just like if you don't want hostile mobs, you can turn them off. You just don't have the option of turning off hunger while leaving mobs on. But you can set the difficulty to easy, which is pretty close to the same thing. Use potions instead of food to regain health. Problem solved.
Or you can find a mod, if it really bothers you that bad.
This has been suggested before, and has been widely discussed.
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I am the bone of my sword
Steel is my body, and fire is my blood
I have created over a thousand blades
Unknown to death, Nor known to life
Have withstood pain to create many weapons
Yet, those hands will never hold anything
So as I pray, Unlimited Blade Works