No idea how it actually is, but I would expect children working in blockbuster to be on the track of careful processes regarding child respect, far more than some random popular youtube channel. Of course abuses can happen anywhere.
Well if YouTube ever turns out someone as messed up as Britney spears or Michael Jackson maybe I'll be concerned but its not like children working in blockbuster/music actually have a fantastic track record
This make me think of the case of Jake Lloyd.