People talk about some areas of the real world as boring because you just see endless wheat or corn fields. Things widely viewed as boring are not going to feature heavily in entertainment products.
People always talk about how reality is too boring, and that's why shows need to have spaceships bouncing around and explosion sounds and superhumans etc.
And then something like The Expanse comes out and it turns out that realism is actually really interesting. Sure, the space is unfamiliar realism, but so is serf life to most viewers. And direction is also very important.
The funny thing about this is that pre modern cities featured in modern media are always surrounded by unformed grassland because it makes the shot more dramatic and it’s easier to do than showing lots of little farms growing in density up to the city walls.
Well, a little diversity in crops wouldn’t hurt. And most of the corn isn’t for humans
In a zombie setting the fact that agriculture takes up a lot of space could be really useful from a story-telling point of view. It provides a reason to expand past the walls of the settlement.
It’s weird because in these settings a successful settlement is usually portrayed as basically impossible for the zombies to break into. Then, somebody has to do something stupid to let them in. Movies where things fall apart despite nobody making an obviously stupid mistake are a lot more satisfying IMO.