John D. Rockefeller established a trust fund to rid himself of competition. This strategy has allowed large oil companies to continue to grow by absorbing any competition. Through such economies of scale Rockefeller was able to reduce costs to such an extent that any remaining competition would not be able to pay the costs of staying in business. The public is concerned because competition is necessary to keep prices low in the long run and encourages the passage of the Sherman Antitrust Act to dismantle the oil cartel. Standard Oil had engaged in price discrimination by offering railroads special prices in exchange for preferential treatment by using railroads to ship their oil. They shipped so much oil by rail that if the railroad lost their business they would lose a lot of it