There is no such thing as normal. Normal is only part of ones imagination. One who claims to be normal, has no true grasp of the reality they live in.
Zombies are the embodiment of a gnawing, constant awareness of the inevitability of death. They never stop. They never plot, or scheme. They can’t be bargained with, or shown sense in reason. They have no meaning, no choice, not even a recognition of the existence of choice. They’re simply forever shambling your way, trying to get just close enough to claw, to grasp, to chew.
Zombies are the anticipation of a gruesome end met at the hands of an as-yet unseen ghoul, who even now may be clambering towards your door.