Has an AFL game ever ended 100-80?
Yes. AFL has seen a final score of 100-80 3 times. It first happened on July 6, 1968, when Melbourne beat Fitzroy, and most recently on August 1, 2010, when Richmond beat Adelaide.
That makes 100-80 the 1534th most common final score out of 6,607 that have ever occurred in AFL. One point away, 101-80 has happened 5 times and 100-81 has happened 4 times. At one point the score disappeared for 36 years, between 1974 and 2010.