Data-Hawk
I have no strings on me.
first, because it's television and they want to be dramatic
second, weren't the first several zombies we see in s01e01 torn apart from the torso i understand what you're trying to convey but most people were probably only attacked once when the outbreak started, and zombies don't eat other zombies.
not only that, if everybody is infected...people who died from natural causes, were murdered( by other humans )..etc.etc came back as zombies.