Discrimination unlawful.

A. It is unlawful for any person engaged in commerce, either directly or indirectly, intentionally, for the purpose of destroying competition or eliminating a competitor, to: (1) discriminate in price between different purchasers of commodities of like grade and quality; or (2) discriminate in price between different sections, communities or cities in this state where the effect is to lessen competition substantially, to create a monopoly in any line of commerce or to injure, destroy or prevent competition with any person who grants or knowingly receives the benefit of the discrimination, or with customers of either. B. This section does not prevent: (1) allowance for differences in cost of manufacture, sale or delivery resulting from differing methods or quantities in which commodities are sold or delivered; (2) persons engaged in selling goods, wares or merchandise in commerce from selecting their own customers in bona fide transactions not in restraint of trade; or (3) price changes in response to changing conditions affecting the market or marketability of goods.