Does the Epic Store allow for games which are free downloads, but where you pay for content directly from the developers rather than through Epic Store purchase

Does the Epic Store allow for games which are free downloads, but where you pay for content directly from the developers rather than through Epic Store purchases? Would that be allowed? Perhaps game developers should ship their games on the Epic Store, and use Epic's resources for management, distribution, discovery, and so on, but handle all transactions themselves so that Epic doesn't get any money out of it. That sounds fair, right?