It's because they don't actually believe a single bit of it.

Sorry folks, but most modern churches don't actually believe what they're preaching.  If they did, you wouldn't have crap like this happening.

A passage from the Koran that denies one of the central tenets of the Christian faith was sung aloud at a cathedral service in Scotland. 

The passage from Surah 19, which specifically denies that Jesus was the Son of God and says He should not be worshipped, was sung during a Eucharist service at St Mary’s Episcopal Cathedral in Glasgow to mark the feast of the Epiphany. 

A video of the recital was posted on YouTube showing a girl singing the passage in a typical Islamic style. It narrates the Islamic account of the birth of Jesus, which includes the claim that Mary was “ashamed” after giving birth, and the infant Christ miraculously spoke from the cradle – something not found in Christian scripture.

People who actually believe that Jesus Christ was the Son of God do not allow a 7th century barbarian death cult to desecrate their church.  Period.  I knew the Episcopal Church was in a downward spiral.  I didn't know they had been corrupted and diseased this badly.