No doubt Scott is a beast, as witnessed in the Sugar Bowl. But as others have mentioned punting isn't only about average.
If your offense can't move the ball effectively, which with Bama seems boom or bust at times, you have a better chance of a longer average. Osu moves the ball consistently and usually picks up a 1st down or 2. They also had the best starting field position and one of the best defensive starting Field positions. That's a testament to CJ being able to pin them deep.