Singing the Scriptures

At our church here in Cusco we love to sing the Scriptures.  Not only do we sing Psalms but also from other parts of the Scriptures like Romans, 1 John, James, Isaiah and other books.  I love singing the Scriptures, well, because the words are biblical.  You can never sing an un'biblical song from the Bible.  Another great advantage of singing the Scriptures is that the congregation memorizes large blocks of the Bible through song.  The church seems to be so alive singing the Scriptures as well.  Just by clapping to keep the beat or using a guitar, and a Bible, we can really worship God in Spirit and Truth.  No need for hymnals because we all have a Bible.  I´m really surprised that more churches don´t sing the Scriptures.  I wonder why?  Feel free to comment if you have some insight on this.  Here is a link to our church web site in Cuzco where you can listen to our church sing from Romans chapter 5, which is my favorite song to sing.