I'm not familiar with the Facebook integrations on the Oculus, can you clarify how the use the these devices would force you to give up your data?
Besides, knowing Facebook's hunger for data, I certainly don't trust them enough to install any piece of their software on my PC. Nor do I trust them enough to use a device which could potentially identify some unique traits of the way I move in VR (akin to gait analysis).
It may also be a bit of a knee-jerk reaction, but in a world where even seemingly innocuous data is used to find unexpected correlations and identify people, I certainly prefer to keep a safe margin of error and steer away from companies which live on our data.