Has an AFL game ever ended 75-8?
Exactly once. On August 27, 1898, Essendon beat Carlton 75-8, and no AFL game before or since has ended that way. When it happened it was a scorigami, the first 75-8 in league history.
That makes 75-8 the 3836th most common final score out of 6,607 that have ever occurred in AFL. One point away, 76-8 has happened never and 75-9 has happened never.