Has an AFL game ever ended 71-30?
Exactly once. On June 14, 1913, Essendon beat Melbourne 71-30, and no AFL game before or since has ended that way. When it happened it was a scorigami, the first 71-30 in league history.
That makes 71-30 the 3836th most common final score out of 6,607 that have ever occurred in AFL. One point away, 72-30 has happened never and 71-31 has happened never.