The special funds herein established shall be used and expended by the officials for which the funds are established by such officials requisitioning expenditures from the fund for the payment of any and all reasonable and necessary expenses incurred in carrying out their official duties, including but not necessarily limited to the following: Official educational expenses for such officials and/or their employees; provided, that such funds may not be expended for the usual and ordinary expenses of operating such officials' office otherwise required by law to be furnished by the county governing body.