By the time Land of the Dead rolls around, the whole world is not only overrun with stinky, shambly corpses, it's mostly adapted to them. People live happy, normal lives in their protected cities, and outside, everywhere else, zombies just rot. Or do they?! They do. But apparently they also evolve, because that's what reanimated meat does. It gets smart. This is already going in a bad direction. But on the upside, most of the featured zombies are wearing costumes, and that's delightful. Zombie cheerleaders are rot-dorable.
Smells like teen spirit! And advanced decomposition!
At the ass-end of the film, as our living hero is driving away in his big, ridiculous zombie tank, he catches sight of Big Daddy, a zombie Martin Luther King Jr., leading a zombie horde away from the city. Instead of blowing them to smithereens like a sensible person might do, he stops and appreciates the view (like a crazy person drinking kerosene and masturbating with sand paper might do), and decides that the zombies are merely looking for their place in the world, and isn't that true of all of us? At the end of the day, aren't we the same as zombies?