That's just it. Fans of Oculus and the Rift were (mostly) interested in the gaming of VR. You have a point, that Facebook can certainly leverage VR to expand their product. But I think it's not in the direction previous/current fans (or even followers) of Oculus were/are interested in.

I'm not necessarily questioning whether this move is in the best interest of Facebook or Oculus. I think both companies will benefit from this long-term.

My point is that this isn't in the interest of the fans/followers of Oculus, and there's no explanation as to how Oculus would be surprised by the negative reaction of those outside the core community.

In fact, the only ones I can think of that would not react to this move negatively are fans of Facebook, and those invested in Facebook and Oculus.