That would have a great kind of symbolism to it; the base instinct of human beings in the form of flesh eaters begets our true nature. Wether it be in the form of scared villagers, or marauding Bikers. I think leaving the island a Zombie infested mess will leave the player with their own perspective of things.
but im pretty sure that within 5 weeks of release some average joe will make a mod disabling the zombie regeneration.....
To each his own i guess
