how does USC get away with their numbering system?

[dawgatUSM]

They have tons of duplicate numbers... 2 of each...1, 2, 4, 6, 7, 8, 10, 15, 17, 18, 19, 23, 25, 28, 30, 38, 44, 45, 49 My only guess is it is some sort of recruiting tool...If so, we need to start making duplicate numbers