Let's just consider a couple of facts:
- The modern running shoe was invented in the early 1970's, and I'm pretty sure that there were people who ran long distances prior to the early 1970's.
- There are still many people around the world who are great distance runners despite not having access to modern running shoes. Many of the great African distance runners started out their careers training and racing barefoot. Of course there are also the famous Tarahumara Indians in Mexico who run in homemade sandals.
My opinion, if you don't already know it, is that it's all about technique. If you have good technique, you can run on almost any surface without running shoes, and if you have bad technique... well, you are going to need running shoes, and you are still probably going end up injured.