As The Crow Hops

The crow hop by a fielder before the throw is made gets the thrower into a strong throwing base...much like a pitcher gets into a strong throwing position by getting into a power position during the delivery. 

Our college coach, back in the day, had everyone (not just the outfielders) crow hop before their throws during pre-game infield. This was done not only as a reminder to get into a strong base before throwing, but to add some 'flash' and showmanship. It gave his teams some identity to go along with a winning record which also certainly attracted recruits for his successful program.