I think it has to be a church, not a church hall. They put it in because otherwise the Three Choirs Festival and similar would not have been permitted. So when you find a church serving real ale let me know!!

If songs are part of a religious service then they are also exempt. That is how we getaway with the carols in Sheffield. The council regard them at Xmas time as part of a religious service and thus exempt even though they take place in a pub.