The placing or maintaining of encroachments by the permission of the council, for which an encroachment tax is paid, or the erecting or maintaining of poles by telephone, telegraph or electric light companies for which permits have been granted by the town are excepted from the provisions of this section 7-1-3. There is also excepted from the provisions of this section 7-1-3 the maintenance of light poles and bus benches placed by the authority of the town. (1977 Code § 12.12.090)