You don't think he went a bit over the top?
It's a dark satire. It's not supposed to a film where turning people into human s'mores is a realistic possibility.
As for the rest of the movie, while it specifically deals with fine cuisine I found it to be a general metaphor for celebrity worship. In this case the insufferable status-by-association results in the loss of these tiny people's lives. I see it as a matter of people like this never having an identity, except that given to them by others. They have some sort of B or C level status, but are far from famous, yet they see themselves as better than the average riffraff.
Thus, lacking any substantial identity they allow themselves to be literally murdered by someone they see as A-list because they have no sense of who they are. This is contrasted by Margo, a high level prostitute who sees all this bullshit for what it really is. She knows who and what she is and doesn't pretend otherwise.
At least that's what I got out of it.