More than two premier grading services and graders.

I am sure many of you subscribe or read coin world on more of a casual basis. I noticed over the years something that seems very strange to me and it concerns grading services. There is one particular salesman, yeah that has one coin show that went defunct and now is on another (shop something or another). I am sure many know who I mean. He is always saying there is only two grading services, that of PCGS and NGC. He calls all others Encapsulation services. I assume for the most part, he refers to ICG and ANACS. In reading Coin World I notice that some of the best articles and knowledge of coins comes from individuals such as JP Martin and Michael Fahey (formerly of ICG now with ANACS). There is one in the current issue written by Randy Campbell (ICG). Why do you suppose he downgrades the companies they work for? Certainly the three individuals I mention, with so much knowledge, know coin grading and are as competent as the graders at PCGS or NGC. I can?t remember an article written by someone from NGC or PCGS, or for that matter Mr. "the line forms behind me".