Gotta teach 'em bro. That's all.
And if sugar won't work, a missle launcher will do.
Either way. It will happen. Simply because the CPM model is only good for branding, and smart companies want more than just branding, and other companies want results and don't give a damn about branding.
Meanwhile, yes, Mainstream Webmasters does offer a CPM model (for the idiots). Natch, none of the adult to mainstream companies want that beastie!