I wonder if a band could put together a live stream concert published to a private stream sent to a movie theater. A bunch of fans of the band could get together and have the concert experience with fellow fans but not have to pay as much as an in-person concert. Movie theaters would have another way to get people in the door.

This definitely happens. Last time Dead & Company came to town, it was simulcast in the local movie theater. Tickets to the show were only available on a raffle basis since the venue didn't hold nearly enough people.

Then again, the Dead were also pioneers of permitting and encouraging the bootleg scene.