When I started working as an usher at the Confederation Centre of the Arts, we had an honest-to-goodness electromagnet in our office. It was used to wipe clean film without manually opening a guest's camera, but mostly, we just played with it. My favourite game was to see how far we could hold the magnet from the metal waste-paper bin to make it clatter across the floor and slam into the device.
It was very unusual to have to destroy film. It rarely came to that, and when it did, it was the manager's Schadenfreude-filled responsibility. As the theatre-goers arrived, we told them not to use their cameras, there was a bilingual announcement before the show, and if a flash went off, we ushers were trained to descend like samurai and tell them to knock it the hell off. It was only the defiant repeat photographer that had his or her camera confiscated and the film destroyed.
The core problem involves the image, of course. The set, the lighting design, and the staging are all protected by copyrights, and the performers are very hesitant to not have control over their images.
Besides the more legal stuff, it's hella distracting to an actor when a flash goes off. If you've ever been in a spotlight, you know that you're working half-blinded; the lights flood your retinas to the point where the audience disappears into an inky abyss. When a flash comes out of that void, it can be very discombobulating. I mean, these performers are seasoned professionals - they're not going to wander, dazed, fall off the stage and into the orchestra pit - but it takes a lot of mental energy to do these shows, and a distraction is a distraction.
It's different, now, with accessible digital cameras and "cameras" in every phone. Where the image was the primary problem and the flash was secondary, now, we have a tertiary issue of audience distraction from glowing LCD screens. Our lizard brains (moth brains?) are so drawn to glowing screens, no matter how amazing the show is, live, on stage, it's very difficult to look away from the tiny-but-shiny glow three rows ahead.
Let me end with this thought: as a spectator, why must we document shows?
Is it to remind ourselves we were there? Maybe the show's not worth going to if we're worried we'll forget.
Is it to share the experience with others? If so, is even a little bit of sharing also showing off? Honestly?
If it's because we're enjoying the show so much, we'll want to see it again, let's consider what quality of experience that will be: the person recording the show is cheated out of the real deal, distracted by the task of recording a tiny, 2D image instead of enjoying the live performance.
Maybe we do it simply because we can. Perhaps soon the novelty of "document & share" will wear off and we can watch a show like a Greek in an ancient open-air amphitheatre would have. I have to be patient. We may come to our senses in a few decades.
I kinda like thinking about the fleeting beauty of a live experience. It's bittersweet, but I love the bittersweet.