The increasing concern about the external costs of alcohol consumption has often led economists and policy-makers to advocate taxes to internalise the social costs and target consumption. However, in certain markets for alcoholic drinks – particularly wine – price is not only a cost but also an indicator of quality, guiding consumer choice. There is, perhaps, a higher probability of ex post satisfaction with products at higher prices in a market with potential adverse selection. The price–quality proxy interacts with discounts, where the full price of the product before discount (referred to as the External Reference Price in the marketing literature) is used as a quality reference.
This study shows that an alcohol tax in the presence of discounting may increase the perceived value of the product, and therefore persuade consumers to prefer the purchase of more expensive wines with the highest discount. As a consequence, consumers could favour products with higher alcohol content – which contradicts the objectives of the policy. Consequently, for an alcohol tax to be effective discounting of alcoholic beverages (in particular, wine) should be regulated to avoid the policy backfiring.