It's not an overall comment on his work or his interviews, as Moore can certainly veer into arrogance himself sometimes. But in this case, I have to respect the takedown of a comment as utterly buffoonish and Snyder's was there.
I mean seriously, what the hell? Anyone who's spent more than two hours in comic fandom knows, Alan Moore doesn't like movie adaptations of his work. Why would he have a DVD of it? Why would he want a DVD of it? Why would he ever watch the DVD on a rainy or any other Sunday?
It seems to me that even if he wanted to express confidence in his product, Snyder would at least acknowledge a worse case scenario being 'Moore never sees it and doesn't care.' Maybe he's being taken out of context, but it really does come off as extremely self-centered, as quoted.