I think it is good example for "bundling" or vertical integration. Like a free Microsoft Internet Explorer (see S. Landsburgs Slate column) the buyer is better off, if the seller offers two complementary goods like meals and toilets in a bundle than a seperate offer. If you are in a restaurant the barkeeper owns a kind of monopoly with regard to meals and a indoor toilet. Of course he can offer both seperatly and get a price where marginal revenue equals marginal costs. If he offers both together he can only charge a lower price (because marginal revenue goes up and thatswhy monopoly price goes down), but the buyer is better off and the restaurant gets more customers.
Steffen
