In a recent interview, Fieri insinuates that he was pretty much forced to wear the shirt in the first place.
If you search Google Images for "Guy Fieri," you're almost certain to see one iconic photo near the top of the results: the spikey-haired chef striking a pose in a black shirt covered in red and yellow flames. This particular picture became popular in Guy Fieri memes, and a similar shirt is the go-to wardrobe option when people look to impersonate Fieri on TV. Most famously, Bobby Moynihan wore a shirt with flames on it when doing his Guy Fieri impression on Saturday Night Live.
Though some may suggest that any issues with Fieri's public persona come from the chef not quite being self-aware enough, turns out the chef is actually acutely aware of all the jokes being made at that flame shirt's expense. According to Eater, in a recent episode of The Sporkful podcast, the topic of this fiery shirt was broached, and Fieri was ready to let his opinion of the button-down become part of the public record.
"I think there's way too much stereotyping. There's a picture of me in a flame shirt that everybody loves. I get that picture sent to me when we do fan mail; it's the picture they send more than anything. And I think people want to love the shirt... 'cause I hate the shirt. We'd opened a BBQ restaurant—and this was way before even the Food Network—we'd opened a BBQ restaurant, and that was one of the shirts that we had. I don't know where we got the shirt or what happened. Goddamn I hate that shirt," he is quoted as saying. "People are going to say whatever they're going to say. People are going to go on their own way about, 'Oh man, everything's flamed at his house.' And I just kind of go, 'Okay, you know, alright. Well, think what [you're going to think].' I mean, what do I wear? I wear shorts and tennis shoes and a t-shirt every day unless I've got to go to work."
Of course, what gets glossed over in that answer is that people constantly wear things they may later regret and the choice simply gets forgotten (or is never even a thing in the first place). The simple fact that Fieri's fiery shirt stuck shows that it resonated with people as a representation of his personality. But regardless, let the record show that Fieri hates the shirt. The hair and sunglasses though… that's all him.