Primarily because both teams used up all the shot clock. Oggy literally had his team dribble the ball by the timeline for 20 seconds, then pass it to Brendon Pocius to instigate the offense with 10 seconds left on the shot clock.
With Pocius driving or getting the ball to Scott, they'd often get fouled or get an offensive rebound and reset the shot clock. So Stetson would have 60-90 second possessions on a somewhat regular basis.
Then Stetson played good defense, made USC use up the shot clock, and wasn't afraid to foul instead of giving USC a good look.
So the shooting % was good, but the number of possessions was probably 60% of what you'd see in a normal game.
Minutes were the same (I play with 12 minute halves).