Take the word "credible" out and I tend to agree with you but if you leave that in then,'Makes sense' means the game world should be credible and consistent. They cannot simply 'define how the world works' without affecting these two properties.
a) Backpack should have at maximum 3 or 4 slots.
b) the bar at the bottom of the screen should have about the same.
c) Rock doesn't stack, iron doesn't stack, pretty much nothing would stack like it does in this game
d) zombies can't punch through anything harder than maybe wood
e) a player can't punch a tree and get wood
f) when a player places a wood frame it should take at least a few in-game minutes to "upgrade" it
g) etc, etc, etc.
The fact you can do ANY of the above is in no way "credible" but it does make a fun a game.