When you can tie a man to the back of a fighter jet and take to the sky with him screaming behind you, does your game really need a plot?
Developer Avalanche is obviously trying too hard. There is really no need for you to have a compelling narrative in a game where I can launch my enemies into mountainsides via a fighter jet. In fact, giving me a story might just be too overwhelming. Look at my time with Grand Theft Auto IV. I spent 10 hours dicking around town, completing maybe five or six missions, passing the remaining time by running all over the place causing mayhem. By the time I got back to the story I found it far too boring to continue.
Just give me wide-open spaces, some stupid enemies to screw with, and a plot that consists of nothing more complicated than X hero goes to Y place for Z reason.