Well take Rapture Pro for instance, it has a demo mode already built which intigrates with CCC, but the package RP hasn't been rolled out in the CCC yet for all users (or users that request it). Still by mistake some paid users got demo versions that didn't get activated (probably because they were offline).
Whatever code they are using here they will probably be using something similar for Sonar eventually, although it will have different behaviour as a demo. And Sonar has a demo mode when it expires from what I understand.
It seems to be that it's just the planets aren't in alignment yet, or more likely CCC is not ready to handle it. Or Cakewalk is waiting till their applications are more stable or impressive, or more likely they are just too busy with everything else.