Railroads justify rate discrimination against captive shippers on the grounds that in the long run it reduces everyone's cost. If railroads charged all customers the same average rate, they argue, shippers who have the option of switching to trucks or other forms of transportation would do so, leaving remaining customers to shoulder the cost of keeping up the line. It's theory to which many economists subscribe, but in practice it often leaves railroads in the position of determining which companies will flourish and which will fail. “Do we really want railroads to be the arbiters of who wins and who loses in the marketplace?” asks Martin Bercovici, a Washington lawyer who frequently represents shipper.

　　Many captive shippers also worry they will soon be his with a round of huge rate increases. The railroad industry as a whole, despite its brightening fortuning fortunes. still does not earn enough to cover the cost of the capital it must invest to keep up with its surging traffic. Yet railroads continue to borrow billions to acquire one another, with Wall Street cheering them on. Consider the .2 billion bid by Norfolk Southern and CSX to acquire Conrail this year. Conrail's net railway operating income in 1996 was just million, less than half of the carrying costs of the transaction. Who's going to pay for the rest of the bill? Many captive shippers fear that they will, as Norfolk Southern and CSX increase their grip on the market.