Reminds me of a thought I once had; do zombies still poo?
I mean, they're reanimated dead folk, so many functions would cease, or operate at a lower level. But they still eat people. Sometimes, it would appear, they eat a vast quantity of a person in one go. However, when was the last time you saw a film like this, or an episode of The Walking Dead with a zombie squatting down in the background crimping off a length?
It's just bloody unrealistic is what it is.
The concept of a zombie apocalypse, though, is well within the realms of reasonable possibility. Of course.