The song does fade out though. I once made a comparative collection of rock songs that used fade out and those which have a clear, definitive ending notes or chords. I found that many bands who made themselves as live acts before recording acts e.g., The Beatles, tended to favor the ending chord instead of the fade out. Once recording studios and gimmickry started to dominate, the fade out increased in popularity. Also, I suspect that radio DJs liked the fade out because it gave them a cue to start yapping again.