1. The supernatural kind. These are animated dead people that want to attack you, and for supernatural reasons are not subject to the laws of nature governing energy, work, and structural support. There is no point in trying to create hypotheticals concerning supernatural zombies, because no consistent rules must apply.
2. Scientifically based zombies. Such as found in the movie “Legend”. These creatures are not dead, but are animalistic forms of humans. They must eat to survive, and they do not need to be shot in the brain to kill them (although it helps). This form of zombie is easy to make rules about, as the laws of nature must apply.
3. Odd combination of #1 and #2 that makes no sense whatsoever, as in “The Walking Dead”. Where the cause is scientific, but the effect is supernatural. These zombies seemingly do not require food, circulation, active nerves, etc., however, they have functioning brains. Their cell structure biology is unexplainably immune from the laws of nature (eyes and ears would be the first organs to become worthless without regeneration). Although tempting to create rules for these zombies, its a fools errand, as they are more supernatural than scientific.
Zombie Apocalypse movies best serve as a metaphor for lawless, animalistic rioters taking over, and good people doing their best to survive in the chaos. Notice how many zombie movies/shows there are and how popular they are. This is a subconscious realization of a lurking danger.
The government-media complex loves chaos in the marketplace of ideas.
Whether it is celebrating serial killers, shark attacks, car pileups, or zombie apocalypses.
interesting breakdown however, i should point out that in the last season of Walking Dead we learned that if you starve the zombies they sort of become submissive. the black gal had two zombies that she used as pack mules. she severed their jaws and arms and kept them on chains. of course the creators dont seem to want to apply this element to the zombie population at large because by now most of the zombies should have turned/starved into this condition which would make for a much less entertaining show.