1.I don't think that the number of zombies that you kill effect the spawn rates. 2. zombies will always spawn back even if you kill every single one of them. 3. If you go to sandbox you can change the zombie density to what ever you want.
Since I love bacon Head: hat made of Bacon Torso: Shirt made of Bacon Pants: Bacon pants Shoes: Bacon shoes Weapon: Frying pan (to cook the bacon) Bag: shopping trolley Supplies: Bacon, bacon, bacon, bacon and more bacon
One of the things I don't get about the cooking skill is that after the power shut off the skill becomes completely useless so why would you level up a skill that would do you no good unless there is still away to cook things even after stoves have become useless.