Many people have never even heard of a crown flash, and many people have certainly never seen one. It is a natural event that is only going to take place under specific circumstances, making it that much more special when it manages to be actually captured on a camera. Thunderstorms create electromagnetic fields, which can alter the position of the ice crystals in the sky.
All the while, light is refracting through these crystals. Since the position of the ice crystals is managing to change, it will look as if this beam of light is moving around, like someone in the sky is waving a giant flashlight. It is incredible to watch. The person who recorded the video is clearly in awe of what is being seen. Plenty of people on Facebook would also be in awe when they were watching this particular video, and they would enthusiastically SHARE it will one another.