One question would set you off on a five-minute rave of anecdote, complete with perfectly calibrated pauses and punchlines. It was a masterful performance actually, but I figured I'd seen enough when I saw a friend of mine heading for the door.
In the interests of minimising the disruption of separate departures and because I wanted to say hello, I joined him. This was too much for you. "Goodnight, guys," you called before telling the rest of the house we could "go and get married now".
Even as I type the words, I find them hard to believe. Yet on reflection, I figure that it wasn't hillbilly homophobia but good old-fashioned megalomania that must have motivated you.
The idea that anyone might dare to turn their back on you could not possibly pass without comment. No matter that there may have been a good reason for the exit (my friend was on his way to another movie; there's a film festival on, you know): anything other than focused adulation is insufferable. This is, let's remember, "all about you".
Of course, anyone who had been paying attention for the previous 90 minutes - never mind your previous movies - already knew that. You are, after all, the man who ate McDonald's, invariably supersized when supersizing was offered, for breakfast, lunch and dinner for a month to - why was that exactly? Oh, yes, to offer the startling revelation, previously unknown to science, that an unremitting diet of junk food is bad for you.
In your next film you made the earth-shaking discovery that Arabs love their children too. And here ...
Here you make a film which purports to be about product placement. The shtick is that you funded it entirely by product placement but the problem is that that's it.
I doubt that there was a single person in the cinema last night who didn't know product placement exists. I know I wrote a piece about it - interviewing a couple of agents in LA - in 1989, when you were still at Woodrow Wilson High School.
What we might have hoped for was a film that told us something about product placement. But only a handful of interviews - notably with directors Brett Ratner and J.J. Abrams - traverse the practicalities, let alone the ethics of the process and about all we get out of that is Ratner saying that if a character is going to be holding a can of soft drink [that's what we call soda down here] it might as well be [insert highest-paying brand here].
You even managed to edit Noam Chomsky and Ralph Nader so they failed to engage with any of the implications of product placement and go along with your goofy trivialisations.
I reckon a process by which multi-billion-dollar multinationals advertise to the world without the world realising that it's being advertised to is a great subject for a documentary film, Mr Spurlock. What a shame you didn't make one here. What you made instead was another hammy, juvenile piece of self-promotion - a 90-minute piece of product placement in which the product was you.
No harm in that, of course. A man has to make a living, and I note your regret that you didn't negotiate a penny-per-page-impression deal because it would have made you $US50 million.
But I don't think that someone who sneaks quietly out before the end of your Q&A deserves to have a sleazy homophobic insult tossed casually at his receding back. Surely you had already got enough cheap laughs.
*You can replay Morgan Spurlock's live chat with nzherald.co.nz here.