Has an AFL game ever ended 37-18?
Exactly once. On July 29, 1905, Fitzroy beat Melbourne 37-18, and no AFL game before or since has ended that way. When it happened it was a scorigami, the first 37-18 in league history.
That makes 37-18 the 3836th most common final score out of 6,607 that have ever occurred in AFL. One point away, 38-18 has happened never and 37-19 has happened never.