Why Do We Love Zombies?

Zombies are EVERYWHERE!! Wait, don't panic- we mean in pop culture, not outside your window. But why is that? Bad guys and monsters seem to go through phases: one decade there's a dozen movies about aliens, ten years later it's vampires. And right now, it's zombies. And monsters don't pop up for no reason at all. There must be something that makes us fixate on one antagonist trope; some qualities they hold that echo a deeper cultural fear... So what are we afraid of now? It might just be technology.