Has an AFL game ever ended 171-78?
Exactly once. On August 30, 1947, Melbourne beat St Kilda 171-78, and no AFL game before or since has ended that way. When it happened it was a scorigami, the first 171-78 in league history.
That makes 171-78 the 3836th most common final score out of 6,607 that have ever occurred in AFL. One point away, 172-78 has happened never and 171-79 has happened 1 times.