Nothing in the law relating to transportation shall be construed to prevent the carriage, storage or handling of freight free, or at reduced rates, for the state, or for any city, county or town government, or for charitable purposes, or to and from fairs and expositions for exhibition thereof, or the transportation of officers, members and equipment of the Kansas national guard, or the free carriage of destitute and indigent persons, or for the issuance of mileage on excursion passenger tickets at reduced rates, open to the public generally, or to ministers of the gospel and those giving their entire time to religious, benevolent and charitable work, or to the inmates of soldiers’ homes, state or national, including those about to enter or those returning home after their discharge, inmates of hospitals, eleemosynary or charitable institutions and members in good standing in the grand army of the republic, or to any railroad officers, agents, employees, attorneys or witnesses, attending court or before the commission, on behalf of such railroad company.