张五常作品

Perfect price discrimination, all-or-nothing pricing arrangement, or the requirement of membership or entrance fees, may all lead to marginal-cost pricing.  The presence of transaction costs may stand in the way of achieving fully this marginal-cost pricing result, but transaction costs may also exist in competitive markets.  If these costs are taken as unavoidable constraints, efficiency may result even if marginal-cost pricing is not attained.  (Monopolies protected by the government have the drawback of not allowing competition to reduce costs and improve qualities, a different and more serious issue.)