The extended cast's relationship to the show
We talk a lot about Tim and Gregg's toxic parasitic relationship with each other -- their inability to leave the other alone, their codependence on each other for platforms, "expertise", etc. -- but something I also think is hilarious is the fact that many of the other characters in the show seem hopelessly drawn into their orbit too. Sometimes they leave, but many of them come back even after being egregiously abused and bearing witness to the worst of Tim and Gregg's narcissism and sociopathy. They just keep showing up, almost as if they buy into T&G's delusions of grandeur.
You would think Joe, Mark, Axiom, Manuel, Toni, Hank from Chaplin's Chili and even the late G Amato would have better things to do than stand around on the set of this cursed movie review show/vanity project year after year, but they are clearly drawn to it like moths to a flame. I think they are all secretly (or not so secretly, depending) hungry for the limelight and relish the opportunity the show gives them to sort of be public figures and communicate with an audience, much like Gregg. Thus they're able to overlook a lot of the abuse and the chaotic atmosphere. They take this incompetently run show far more seriously than any logical person would.
It's one of my favorite things about the universe; not just that the two hosts have such an unhealthy dynamic, but that there's an entire toxic inner circle of people, like a cult, whose members have occasional lapses of reason and branch off -- but usually end up bouncing back to be abused more.