I guess the justification for such songs is that they're really easy to learn, and teach to a bunch of school kids.The one I really detested was "Reuben and Rachel". They used to divide the class into males and females and force us to sing alternate verses. What torture! (specially for the boys, who were mostly embarrassed out of their minds).
Mind you, I'd really like to hear William Shatner's version of "Reuben and Rachel" sometime. I have the feeling he could give it a whole new twist.
- LH