But isn't the game's representation inspired by Romero? I'm appealing to Romero because I'm saying it does fit with the game's representation of zombies. The idea that it doesn't is entirely down to a preconception of "zombie-ness". They're customisable, anyway. Sprinters, supernatural strength, opening doors. There's a wide but limited range of what entails a zombie and the devs seem happy to work within that range. Like in the Walking Dead/World War Z, zombies will eat anything alive. Including animals. In Romero movies, they only eat humans. Devs have said zomboid zombies will not eat livestock or wild animals, and they don't currently eat what you trap. Why do they only target humans? If they're hungry, they should target anything. But it's not actually intelligent, on their part, it's just basic stimulus - reaction that obeys an ultimately arbitrary set of rules. Why don't they attack impassable barriers? Maybe it's gameplay, but zombie fiction will rarely show a zombie scratching at a concrete wall when they heard something at the other side, certainly not if there's a wooden door nearby. How do they know the strength of materials? They also know how to get to places. If they see you on the third floor, how do they know how to find stairs and climb up to you? That's complex navigation that a lot of animals would struggle with. Why do they horde? It can be explained by a shared stimulus making an ostensibly social behaviour but you'd expect them to quickly drift from one another. Zomboid has a "horde leader" mechanic which might just be for gameplay reasons, but is also seen in Dawn of the Dead and Land of the Dead. Why no "guts" camoflauge like in the Walking Dead? Hard no from the devs on that topic. How could it be impossible to fool a mindless creature?
There's a radio story where a man escapes his zombified sister by swimming from a small lake island. He reurns, later, and sees her standing there still. Why didn't she follow him into the water? Does this mean zomboid zombies avoid bodies of water? Maybe the zomboid devs thought the World War Z image of millions of zombies wandering into the ocean was just a bit silly.
The "scientific zombie" explanation is that it's a virus that hijacks the brain, preserving only the most necessary functions for feeding. Why can't avoidance of fire be a preserved instinct? Seems so silly to me that that's somehow crossing the line. Behaving erratically when set on fire implies some sort of reaction to fire, anyway.