I'd say it's thought provoking in the sense of the entire time you're thinking.. what the heck is going on.
It's the kind of film that you believe they're holding on to some more dramatic detail so you continue watching and waiting to discover this in hopes it gets better only to realise you were wrong.
You assume there's always one character you want to not die, one that you grow fond of... but in this movie you have no attachments to the characters. By the end I wasn't concerned if the zombies lived, the humans lived.. even if the stray animals lived.