This is an excellent complaint, and it has been raised before by users (https://discussions.apple.com/thread/3192014?start=0&tst...) and bloggers (http://www.tuaw.com/2011/08/02/baffling-inconsistencies-in-o...). It's a UI inconsistency which makes no sense, is confusing for users trying to scroll, and causes problems for developers.
Regarding reverting it, the following Stack Overflow question and answer seems to have found a solution via a github plugin:
http://stackoverflow.com/q/8737709/168775
I have no idea if it works. Good luck!