It's not the same thing though and the microsoft blunder was not a BTS video. And it also isn't a PR slip up by showing whatever you shot on in your BTS. You do realise Sony didn't shoot the advert even though they commissioned it? Sony made a much classier advert that didn't need the plane painted with their logo or the skydivers all wearing Sony outfits and so on. They already have a HUGE name unlike GoPro that must have their logo on your shoelace sef
Ok let's look at the Nikon advert you posted. Why did Nikon make 'we shot the entire commercial on it' a big part of their selling point? Because prior they have so lagged behind in the DSLR video-capable game by releasing rubbish after rubbish cameras when they were infact the first with the D90. So it was a BIG DEAL for them to say that... Oh and by the way many other commercials have said the exact same thing yet it turns out to be *ahem* a completely different camera used... just saying.
No worry about wetin they take shoot unless they specifically want to use it as a selling point like Nikon did in this ad. Na Internet trolling start the "Shoot your spot with the camera you are selling" and those trolls are the ones that never have any works to show... for real. Don't mind them, no let them feed you their silly ideas... oh they have none.
I don't even think RED or Arri shoot all their spots with their own cams. They can but they do division of labour and usually hire a filmmaker that they think will do the best job of making their advert.