Forcing users to violate their personal moral principles, upon which the decision of never using anything related to Facebook rests, is a big enough difference for many--myself included.

EDIT: I didn't know that Facebook bought Oculus some time ago, back in 2014--for some reason I thought it happened far more recently. I would make the case above for someone who had bought an Oculus device before Facebook's acquisition and now would be forced to use its platform, then. I don't have anything to do with Facebook, personally. I don't even use WhatsApp, so there's that for my moral integrity.