It shall be unlawful to entice into a service station, store, expose for sale, or sell petroleum products so as to deceive or tend to deceive the purchaser as to the nature, quality or identity of the same by false representation or by substitution, mixing, blending, or adulteration, or by the use of disguised signs, camouflaged or falsely labeled containers, tanks, pumps, or other dispensing equipment, or by imitating the design, symbol, or trade name under which recognized brands of such products are generally marketed. It is provided, however, that nothing in this chapter shall prevent a person, firm, association, or corporation, or their agents or servants from storing, exposing for sale, or selling any such petroleum products under the trade name, sign, symbol, or distinguishing mark adopted and used by such person, firm, association, or corporation in good faith, if such trade name, sign, symbol, or distinguishing mark is not deceitfully similar to that already in general use by any manufacturer or seller of such products.