If zombies would exist in Unturned, they would have to find many ways to survive other than eating you, if zombies are an infection/parisite they would still have to eat drink Keep warm and keep every other part of them functional here are a few ways that zombies could do that
The Food Problem
Although zombies are meant to eat people, as we can see in most zombie apocalypse games that food source is long gone. A food source that most people think of is animals and while that is a good food source zombies would have to be good hunters and flankers how would zombies do this? Well if they can ambush a base with a horde they can most likely hunt animals another food source may also be crops, yup zombies could be diggin out your potatoes for food
Gonna need a drink to wash that down
Yup zombies are gonna need water, due to it being vital for survival even zombies are gonna get thirsty. There are a few ways for them to get water such as drinking from lakes or toilests
( ͡° ͜ʖ ͡°) maybe there would be zombies scattered across lakes or water sources.
Yup im talking about zombies getting sick, maybe the infection/parisite could defend against this kinda stuff which is unlikely, or maybe you would see zombies randomly dying or even clothe piles with random loot scattered across the map due to infection or zombie sickness
How Zombies Would Hunt
Zombies are pretty stupid but if there smart enough to horde the player, they can definitely hunt, your probably not there only food source. How are ways they could hunt ?
Outrunning the animals
Zombies can run pretty far which could tire the animals causing them to get eaten by zombies
They are also pretty quiet which could be a good way to flank the aninals maybe they could even surround the animals which is very unlikely
Yes even zombies follow physics they need lots of things to survive same as we do