This is a bad example and a common misconception. Standard Oil was an efficiency monopoly. It was a tremendous boon to consumers:
Instead of buying oil from jobbers, they made the jobbers’ profit by sending their own purchasing men into the oil region. In addition, they made their own sulfuric acid, their own barrels, their own lumber, their own wagons, and their own glue. They kept minute and accurate records of every item from rivets to barrel bungs. They built elaborate storage facilities near their refineries. Rockefeller bargained as shrewdly for crude as anyone before or since. And Sam Andrews coaxed more kerosene from a barrel of crude than could the competition. In addition, the Rockefeller firm put out the cleanest-burning kerosene, and managed to dispose of most of the residues like lubricating oil, paraffin, and vaseline at a profit.
Between 1870 and 1885 the price of refined kerosene dropped from 26 cents to 8 cents per gallon. In the same period, the Standard Oil Company reduced the [refining] costs per gallon from almost 3 cents in 1870 to 0.452 cents in 1885. Clearly, the firm was relatively efficient, and its efficiency was being translated to the consumer in the form of lower prices for a much improved product, and to the firm in the form of additional profits.
It is difficult to overstate how much Standard Oil revolutionized the oil refinement process, resulting in oil that was significantly cleaner and cheaper than its competitors’.
Instead of buying oil from jobbers, they made the jobbers’ profit by sending their own purchasing men into the oil region. In addition, they made their own sulfuric acid, their own barrels, their own lumber, their own wagons, and their own glue. They kept minute and accurate records of every item from rivets to barrel bungs. They built elaborate storage facilities near their refineries. Rockefeller bargained as shrewdly for crude as anyone before or since. And Sam Andrews coaxed more kerosene from a barrel of crude than could the competition. In addition, the Rockefeller firm put out the cleanest-burning kerosene, and managed to dispose of most of the residues like lubricating oil, paraffin, and vaseline at a profit.
Between 1870 and 1885 the price of refined kerosene dropped from 26 cents to 8 cents per gallon. In the same period, the Standard Oil Company reduced the [refining] costs per gallon from almost 3 cents in 1870 to 0.452 cents in 1885. Clearly, the firm was relatively efficient, and its efficiency was being translated to the consumer in the form of lower prices for a much improved product, and to the firm in the form of additional profits.
https://fee.org/articles/41-rockefellers-standard-oil-compan...
It is difficult to overstate how much Standard Oil revolutionized the oil refinement process, resulting in oil that was significantly cleaner and cheaper than its competitors’.