My friend, this is a fine slogan but is it true? Christ's Body is where Christ's Spirit is. A church is a building or an organization. Unless there is true devotion to God there is no Christ's Body. And if there is a true devotion in a desert then there is Christ's Body.
St. Francis of Assissi was so much devoted and in tune with Jesus Christ that he had unity in body, mind and soul with Jesus Christ. That is why he also had Jesus's wounds of crucifixion on his own body. This I call Christ's Body. As far as various churches of the world are concerned - no, in most cases they are not the Body of Christ, they are simply places to gather and listen to sermons without much devotion really.