Fans is short for fanatic and all fans are fanatics. First of all, Andrew Luck does not owe fans anything. I am being realistic, fans did not pay Andrew Luck but Jim Irsay did. Jim should have took some of the money back from Andrew Luck but things would probably get ugly. The Lions took money from from Barry Sanders and Calvin Johnson when they retired prematurely but Colts handled with class.
Most of the fans did not boo luck but the ones who did had every right to. Luck announced his retirement 2 weeks before the season started so fans have the right to express frustration. Some