There is no one state that can lay claim to being the only home of rednecks. What causes folks to be classified as a redneck is usually left up to each individual's own interpretation. Posting signs that say you will shoot people for doing different things is one way to be classified as a redneck.
I found this redneck example on flickr.com (you can spend hours looking at many lovely michigan photos, but today I wanted to find something strange). Supposedly this picture was taken in Kalamazoo. You see rednecks don't just live in the country, they can be townies too. Note the kid's toys in the photo, I don't think you should be discharging firearms with children present.
You also should not speed through residential streets (or any street for that matter) and as a parent I can sympathize with wanting to do bodily harm to someone driving recklessly with children around. What helps classify this as "redneck" is the fact that only when harm comes to the sign owner's dogs is anyone liable to be shot. I think the sign is a hoot!