Posted: 2/28/15 at 8:36am
Because the award wasn't for the songs, it was for Scoring of a Musical Picture.
Just like Herbert Stothart won for scoring The Wizard of Oz. The award went to him, not to Arlen and Harburg (who won for the song Over the Rainbow).
It's akin to adapting a screenplay.
They later changed the category many times to Best Song Score or Adapted Score (to include the composers), then changed it back, then dropped it, etc.
A tricky category.
"Jaws is the Citizen Kane of movies."
blocked: logan2, Diamonds3, Hamilton22