I too thought it was interesting that Brecht came back with this new breakthrough, the first thought that jumped into my mind was the obvious one.
I don't know Ton personally, but I think we all look up to him and respect his judgement. There is no way that he will allow the code to be simply copied or stolen. I wouldn't worry about that. Brecht has definitely started this from scratch, and when it is released the whole world including RS will likely benefit from the code inside. And this thing is a long way off from being ready.
I love octane and suggest it to everyone I know in the industry. I think that cycles will give hobbyists a taste of what they can get from a real gpu renderer. Professionals are more likely to buy something than use FOSS, just so they can get support if they run into trouble if nothing else.
All that being said, if I was on the Octane team, I would probably be mad too.