It is unlawful for any person engaged in the distribution or sale of merchandise of general use or consumption to sell such merchandise at less than the cost thereof to such vendor with the purpose or intent to injure competitors or destroy competition. Any merchandise offered for sale at a price below cost shall be prominently displayed in the outlet offering the same in sufficient quantities to meet the usual and reasonable expected demand therefor.   [PL 1965, c. 305 (NEW).]