It is church law, laid out in each Archdiocese. Music for weddings is also controlled by the archdiocese. Years ago a neighbor was killed in a semi accident. At his funeral there were 5 tractors parked outside the church in his memory. The priest at that time allowed them to play a CD, a truckers song. The casket was wheeled up to the door of the church after mass & the song was played. Times have changed in the church.