Ad selection in opt-in media experience based on multiple group membership and participation

A system to deliver media over a network for rendering by client devices, the system comprising:

• at least one memory that stores computer-executable instructions;
• and
• at least one hardware processor that, when executing the computer-executable instructions stored in the at least one memory, is configured to:
• operate a hub between a Subscriber Information Service and a Content Information Service to identify a plurality of distinct upcoming shared media experiences that a particular viewer is opted into based on subscriber groups formed in a Subscriber Information Service and media events and an association of one or more opt-in groups to the media events defined in a Content Information Service;
• select supplemental media to alter a particular one of the distinct shared media experiences, the selecting based on the plurality of distinct upcoming shared media experiences that the viewer is opted into;
• and
• during digital delivery of the particular one of the distinct shared media experiences to the viewer, alter the particular one of the distinct shared media experiences with the supplemental media and with additional supplemental media selected based on additional actual viewers of the particular one of the distinct shared media experiences, and direct the supplemental media or additional supplemental media to a device other than a device that initiated the shared media experience.