I think the stats for Episode 1 are skewed by the fact that if you try to reason with Larry in the drugstore, the game counts it as you siding with Larry. Which doesn't make a whole lot of sense, and I'm guessing that confused quite a few people. I made that mistake myself on my first playthrough and ended up going back so I could side with Kenny in the drugstore.
I was basically with Kenny 100% up until the meat locker in Episode 2. IMO, Kenny crossed the line on that one. Then the jerk left be to be killed by walkers at the beginning of Episode 3. After that, it's all over. Forget this guy. He only cares about himself.