The Era of Free Throws - another statistical oddity

Of the players in the top ten career Free Throws Attempted category, three of them were from the same class (1955 their final year). What makes this odd, is that none of them would be household names to anyone but diehard fans of that program: Wake Forest's Dickie Hemric, Indiana's Don Schlundt, and Penn State's Jesse Arnelle. It would make sense if the names on the list were Pete Maravich, Oscar Robertson and Ralph Sampson, or some trio of all-time greats; but what caused these three particular players to be the object of so much fouling in those particular years?