Well, the story does take place in the South. The second amendment certainly appears to be well-supported. There may be an allegory here, in that slaves had no rights and were at the mercy of the white (human) population. This could be reading too much into it too, I imagine.

 

It doesn't explain the fast-moving zombies, like in 28 Days Later or Zombieland or World War Z, but it helps explain the slow lumbering ones that cause so much fear in the Walking Dead.