Were Roman collegia only social clubs? There is no simple answer to this key question. Professional collegia were no firms and were much more social than economic institutions. Yet, as private representative associations, they could defend members’ professional interests with civic authorities. So, why did the nautae Rhodanici honor their indulgentissimus princeps Hadrian in the very small town of Tournon-sur-Rhône? We suggest that they received a fiscal privilege, perhaps corresponding to the exemption of a toll