Imagine settling in for a cozy night in front of the television screen. You’re in the mood for something light, so you slap on Project Runway, or maybe an old reality show like The Hills if you’re feeling nostalgic. Are you scandalized to learn that these shows are heavily edited, or even scripted? Would you prefer to watch things happen as they really might have—Lauren Conrad and co. acting like co-workers instead of archnemeses—or do you get a kick out of the dramatized catfights and mascara-smudging tears?

Similar questions have come up with nature documentaries. In 2011, it was revealed that the venerated BBC series Frozen Planet had filmed its footage of newborn polar bear cubs in a zoo. Is this footage misleading? Yes, since it’s presented in the context of wild polar be...