And seeing as how Hollywood grade editing software is available to anyone with a computer (and that's everyone), more and more of these things are being very convincingly faked. Multiple witnesses / angles? Eh, so the editor got some people to play along.
I'm not saying this to say that I absolutely 100% disbelieve everything I see. The video above, for example, has very much piqued my curiosity and if it is in fact genuine I would love to know what the hell it is we're seeing - even if it turns out to be something "boring". I'm simply saying this to remind people to take what you see on the internet with a grain of salt.