The other question is who would staff this ‘paid version’ sub-forum, surely not those volunteers using the free version (whose only concern is helping other avast users) if there were to be segregated sub-forums.
Not only that it would make the forums much more messy and harder to find/follow issues which can be present in both free and paid versions. Certainly this topic would fall into this category as virus definitions/detections would be the same across the board.