The First Seven Roman Governors of Judea

Rome permitted Judea a degree of self-governance until Augustus banished Herod Archelaus, incorporated Judea into the colony of Syria and appointed governors directly from Rome. This is what puzzles me: the seven governors who followed all had oddly plebeian names, despite being, all of them, noblemen: Coponius ('Shopkeeper'), Ambivius ('Two-face'); Rufus ('Redhead'); Pilate ('Javelin Man'), Marcellus ('Droopy') and Marullus (‘Catnipper’). Why's that?