It seems like almost no one can be famous for a considerable period of time without becoming an insufferable whatever.
Think about the reality distortion zone around a celeb. They can't really trust anyone or not wonder about their motives and interactions, from TMZ to crooked investment schemers to glad-handers and people who just wanna somehow be in their shadow. Many normal people just act weird and giddy around celebs.
Plus, there are so many people for whom celebrities' success smacks them in the face of their own personal failures or perceptions of sorts....I always call it the "high horse" thing, where someone is always trying to knock someone else down notches because they dared to stand up and be noticed. It's very tiresome and it happens often within families.
I always got the impression that Fieri is just a Sonoma Cty bro' who got famous and all the others around him just love to find a flaw in character, a slip of the tongue whatever to then fixate on for life. People just do that.
And people who have celebrity often have that burning inner need to be recognized. It's not a pretty thing.
All the fame in the world doesn't solve a person's inner issues, in fact, it seems to amplify them, I say, on the week of Robin William's suicide.
Don't know the guy (Fieri) though my family up North have friends who have known him and had varioys interactions.. don't care much for the show but it doesn't surprise me that he might come off that way to at least someone.