He doesn't do it because he's insecure, he does it because a) working in a kitchen is stressful b) you don't become good at something by being babied and given a gold star for every little thing you do, and c) it's reality TV. The more he acts up, the higher the ratings will go

>Owns multiple successful high end restaurants around the world
>Has starred in several successful reality tv shows
>Gets paid to yell at people on television
>Obviously insecure

Ok then, OP.