Ma-Bell and Standard Oil were essential services, Facebook is entertainment.
Of course, my sister uses her telephone connection for entertainment as well..
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.
Cars didn't run on something Standard Oil did not sell.