from YA's linked article, this was the only thing I found surprising:
"Although Tom Petty had reduced his smoking to one pack a day..."
when that's considered an accomplishment... 
he was a great one. one of the best SB halftime performances, too, as far as I'm concerned. lived his life the way he wanted. I always appreciated that he brought his family on tour with him.
http://www.houseofhere.com/petty.html
He's 40 years old now. There are metal bones in his right hand to replace the ones he atomized when, in 1985, he slammed his fist into a wall out of frustration with his music and life; it took a lot of physical therapy to get it working again, but nowadays he notices the metal bits only when the weather gets very cold. He's had surgery on his right knee, wrecked from years of "leaping off drum risers"; his left foot is arthritic, possibly from pounding it onstage in time to his music. "I have to survive on medication the rest of my life in order to walk," Petty says. "That's something I can deal with, I suppose." "A lot" of hearing in his left ear is gone; both ears ring. "I feel sometimes like an ex-football player. I'm just becoming aware that my body's been beat up really bad."
as Dan Hicks said: "You probably think it's easy being up here, singing and everything and playing. It's not. It's not easy. Thank you."