I find it really amusing when restaurateurs on Kitchen Nightmares say things like “who is he to tell me how to run my restaurant” because it’s like he is an internationally-renowned millionaire Michelin Star chef and you are a person with a failing potato cafe
Also, you literally invited him to come and tell you how to run your resturant…
Actually, that is the very reason he yells at them. Because they don’t listen and they don’t learn. They make excuses rather than try admit they made a mistake. If you’ve seen him work with kids, you know he is actually a very kind teacher as long as the student is willing to listen.