28. The city council may grant or refuse licenses, and may require taxes to be paid on such licenses to agents of insurance companies, whose principal office is not located in said city; to auctioneers; to public theatrical, or other performances or shows; to keepers of billiard tables, ten-pin alleys, and pistol or rifle galleries; to hawkers and peddlers in the city, or to persons to sell goods by sample therein; to agents for the sile or rcnting of real estate; to commission merchants, and all other business which cannot be reached by the ad valorem system under the preceding section. They may also grant or refuse such license to all sellers of wine or spirituous or fermented liquors, and require taxes to be paid on such license in addition to other taxes imposed.