Originally Posted by Chrizza
The guy was impaled, Kenny should know better than to try and save him. Putting him out of his misery is the only option from the second you see in what condition he is.
That scene was more about what makes sense to Kenny rather than what makes sense to us. Kenny had realized how selfish he acted throughout the ZA, and did what he thought he had to do to redeem his integrity. Sure, from our point of view he could have ended Ben's misery right away and left with Lee. But from his point of view, trying to save Ben regardless of how little sense it made was the only right thing he could have done.