You can get by pretty well on 1 mre per day. That's not saying anything bad about mre's (well, not necessarily).
True, but if this is a BOB, you should have more than one.....if it is a GHB, well then one might be fine.
When you have a gun and ammo, you don't need to pack around a bunch of food and water. Just the items to cook the food and drink the water.
or hunt............So, by your statement, it sounds like you intend to take whatever you need from others....