Kettles, almost by definition, do NOT pay for extra legroom, upgrades to First, etc. However, lower level elites as well as general business travelers often will. These are cash cow, if not golden goose, customers, who can add a significant additional revenue stream for CO over time. This, really, is only a "movement" on behalf of the top tier elites who stand to loose the most with these new options. As a result, I doubt that it will gain much traction with either CO or most regular flyers.