I'm going to take issue with both of those comparisons. Standard Oil was only a dictating force in the economy for a short while, after it took over every other oil distribution company. Oil is a dictating force, the company was simply an outgrowth of scarcity rent.

Ma-Bell was in fact, not the only way to communicate. That's like saying Phones were the only way people got in touch. Its simply and patently wrong. as far as industries that did Ma-Bell's job, you've the post, television, and radio.