That is starting to change. The New York Metropolitan Opera is broadcasting eight operas this year, live, to over 600 cinemas around the world (with an encore presentation of each opera a few weeks after the first date) in a series they call HD Live. That's a whack of dough.
The Met was always richer than most other opera companies. Prices are higher and the hall seats 4,000 people, which is exactly twice as many as Toronto's Four Seasons opera center.
The Four Seasons is a far better place to enjoy opera. No seat is further than 90 feet from the stage, and all seats have not only great views but also glorious sound. I recently had a conflict with a performance in my season's ticket and had to take a replacement seat in the fifth (top) tier - it was great. I could see perfectly and the sound was in some ways better than the ground floor, where the orchestra slightly overpowers the male singers. (Never the females: a classically trained soprano is the loudest thing produced in nature.) Also, there are decently priced seats at the Four Seasons (my ticket in the fifth tier was $35), whereas at the Met the only cheap seats are the three rows of standing room at the back of the orchestra and first balcony, which are truly crappy ways to see an opera, and which cause problems for the people who purchased the $200 seats at the back of the ground floor, because the standing room people regularly pour into seats they think might be empty, causing late-returners to have to call the usher and make a fuss.
Cinemas in Canada charge $23 to see a performance of the Met. The performances in my home town are so popular that the Conestoga Mall Galaxy theater sometimes opens up a second cinema for them. If there were an average of 200 people at each performance, that's 23x200x600 = $2,760,000 per performance. Compare that to what they pull in at the opera hall: at an average price of $200/ticket, a performance grosses 200x4000 = $800,000. For the season, the cinemas bring in 16x2,760K = $44,160,000. That's gross of course, and would be offset by the cinema's cut and by production costs. But still - it's a whole new world. I hope the musicians and staff are seeing some of it.
The first time I saw a Met performance in the cinema it took me a little while to get used to the lack of directionality of sound. The sound quality was fantastic but live operas aren't miked, so when someone sings you can hear the voice coming from their body. After half an hour I got used to the lack of directionality, and it hasn't bothered me at subsequent performances.
In some ways the cinema version is better. The Met uses eight cameras, so the visuals are far better than you could get in the best seats - which, even if I could afford them, have been permanently reserved by season ticket holders. The quality of the Met productions is nonpareil. They have the best directors, set designers, singers, and so on. Not that small companies can't be just as good, but the Met is consistently mind-blowingingly good.
My local opera company (variously called Opera Ontario, Kitchener-Waterloo Opera and Opera Hamilton, and currently on hiatus because of financial difficulties) put on a production of Gounod's Romeo & Juliet a couple of years ago that is an example of a small company doing extremely well. Juliet was sung by up and coming Canadian soprano Laura Whalen. In the early, happy part of the opera she literally bounced with joy as she sang. Everyone in the audience watched her with a huge smile on their face, riveted. Her voice was high and pure, perfectly suiting a young woman in love.
Today's Met performance of Romeo & Juliet had a very different feel. Anna Netrebko as Juliette is almost a mezzo: her voice has an older, darker sound and a lower register. At first I thought she was poorly cast, but quickly I began to see that the casting was brilliant. Her voice evoked angst and pathos in a way that explained the action. The whole production was mesmerizing and I won't miss the encore presentation on January 5.
The Met isn't the only opera company that is expanding into cinema. The Princess Twin, an independent cinema in my town, has inaugurated an opera series this year they call "any company but the Met". Their operas aren't live and the filming/editing isn't quite as top notch, but they're also shown in High Definition and the sound is also phenomenal. Plus, it gives us a look into opera houses around the world.
As to who attends the cinema operas, they look like the same people I see at live opera only they're not as dressed up. Another difference is that nobody coughs. In the production today, I could hear people in New York coughing, but not a single person in the cinema audience. The great freeing thing about the cinema version is that I am not required to clap - I loathe clapping - and when the singers are taking their bows, I can get up and go without offending them. I like to leave an opera with the music in my ears, which 15 minutes of curtain calls messes up.
The next step in cinematic opera should be Wagner's Ring Cycle. The Met is rumored to be planning one last production of its classic rendition of the Ring Cycle, and they should offer it to the world in cinema format. The world might never be the same.