Because I went to Catholic school for k-8, have been to mass more times than I can count, and the Church is the founder of Christianity, tracing its roots back to Peter. So I do count on it, as the expert in the field and the original creator of the Christian Bible, to get the faith correct, even if I no longer have any myself. It's been attempting to answer questions of faith for literally millennia, so you'll have to pardon me if I give its answers more credence than I do someone who is essentially a self-taught weekend warrior in the field.
And more to the point, just because you happen to take the paradoxical stance that half the Bible (or really, just the four gospels that happen to have been chosen by the Catholic Church for inclusion in the Bible) is literally the word of God and rest isn't, doesn't mean that the vast, vast majority of Christians make that same distinction. Catholicism and the major protestant denominations all treat the entire Bible as the word of God, not just the New Testament and certainly not just the four gospels.
