It's not a "need", I don't think, to feel that we are in possession of the Great Light, but the reality that God came into time in the Person of Jesus.  While there are other faith traditions that may possess elements of truth, its fullness resides in that Church founded by Jesus.  One may certainly choose not to believe that, but many of the faith traditions to which you point engender far more incredulity than a monotheistic faith with a personal God.  Yes, there is no certainty in some instances, like the fate of the individual unbaptized, for example.  But that which is key to our salvation, like our relationship with God the Father or the resurrection of Jesus are just a few of those certainties to which Christians can point as touchstones to their faith.  Far from patronizing, it is recognizing that all are called to this relationship and God has granted a way for them (and us) to answer that call.