In addition to the license tax levied, assessed, collected and paid in respect to sales of alcoholic liquors, as provided in § 12-33-230, there shall be levied, assessed, collected and paid in respect to such alcoholic liquors an additional tax of five cents upon each eight ounces, or a fractional quantity thereof. Provided, that for alcoholic liquors offered for sale in metric size containers there shall be levied, assessed, collected and paid a tax at the rate of twenty-one and one hundred twenty-five one-thousandths cents per liter.