What difference does it make?
So you opt out of tracking. Facebook’s aggregates an enormous amount of data on people, as does google and others, but facebook is in a unique position to know where you live, work, and who you network with) and they can do almost all of that without using the app itself as a direct conduit. Once you post something, they can cull it out through your networks.
As if Facebook won’t go ahead and track you anyway.