(1) commodities sold for immediate consumption on the premises where sold;
(2) vegetables sold by the head or bunch;
(3) commodities in containers standardized by a law of the United States Virgin Islands or by federal law; or
(4) commodities in package form where there exists a general consumer usage to express the quantity in some other manner. The Director may issue regulations necessary to assure that amounts of commodities sold are determined in accordance with good commercial practice and are so determined and represented as to be accurate and informative to all parties and interest.