The city manager may prescribe stands for vehicles for hire. When such stands are prescribed by the city manager such vehicles shall be parked in such stands, and such stands or locations shall be restricted to vehicles for hire, and no other persons shall use the same for parking purposes. Preference shall be given in establishing such stands to vehicles for hire in the order of time in which the owners or operators thereof have heretofore operated vehicles for hire in regular service in the city, preference being given to operators who have operated such vehicles a greater length of time. (Prior code § 21-9)