About the "zombies would be eaten in days" reason: Wouldn't eating infected meat just mean whatever's causing the zombie outbreak gets transferred to the animal? ._. The article doesn't stipulate that the virus only effects humans. And even if the animal is somehow immune to the virus, what if they somehow become carriers? ._. Hell, what would happen if fleas end up being carriers for the zombie virus? What if mosquitos become carriers?
Also, I don't think this article takes into account fast zombies.