See, most of zombie fiction usually concerns a group of survivors. The crux of the tension is how these survivors have to navigate the day-to-day hardships of living in a post-apocalyptic world. Not only do they have to deal with fighting off the hordes of brain-munching undead, but also the dickish human-beings (the apocalypse seems to bring out the worst in most people).
My philosophy is: why bother with all that survivor bullshit? What good will it do to you? Regardless of what you do to survive and sustain yourself, you will live in a bleak, depressing world, full of rotting meat and depleting resources. Lack of food; no family; no promised well-being; no reliable internet connection and no hilarious cat videos to pass time.
Which is why I would rather be a zombie.
As a zombie, you can mindlessly roam around in an all-you-can-eat buffet. You can spend all your time hanging around with your, amazingly cool, undead brethren. You can go where ever you like, and do absolutely whatever you want (as long as it doesn't involve using brain cells).
No need for all that survivor bullocks and the anxiety that comes with it. It's so much more relaxing to get bitten by a zombie in the beginning and convert to the new zeitgeist, rather than spending all your time trying to avoid getting bitten, only to live in a grim world.