Listening to commentators on NFL games, it seems that all of them systematically call the ball "the football", and not just "the ball".
Why is that the case? In Rugby or Soccer (at least in my country) I've never heard commentators call the ball "the rugby ball" or "the soccer ball". There doesn't seem to be any advantage to calling it "the football", which is longer and not really more descriptive.
"Football" is the name of the sport. Why do comentators insist on calling the ball it is played with the same name as the sport itself?