Store Promotion, Manufacturer Competition And Welfare

This study evaluates the partial exclusion effects of store promotion. We find that a manufacturer with a better brand name has a higher willingness-to-pay for promotion services offered by retail stores or online platforms. The promotion results in higher sales-weighted average prices (wholesale and retail) and a larger inter-brand price gap. The stores or platforms extract more profits from manufacturers and consumers through the promotion services. The effects on consumer surplus and social welfare depend on whether the promotion alters consumer preferences. If it does, more consumers would be choosing their less-preferred brands because of the larger inter-brand price gap, which would be socially inefficient. If it does not, the promotion may help to correct the price distortion, but the social welfare effect is positive only when the promotion effect is small enough. In both cases, the promotion services reduce the total consumer surplus by softening inter-brand competition.