As for Anita Bryant, it wasn't her music that Buffett opposed - it was her stance as an anti-gay rights activist.
The story I heard about Anita Bryant in a Buffett interview was that early on in Jimmy's career one of his songs was offered to Anita to sing. When she heard the song in the studio she roundly rejected it. Jimmy was "offended" and declared "And I hope Anita Bryant never ever does one of my songs....."
Funny how many stories there are for these things
