I'm not familiar with Gopnik's take on wine, but as restated by Geo, I couldn't agree more with Geo's response.
As far as "moralism" goes, I do think that there's certainly a lot of silly, "Portlandia"-style eating by narcissistic people going on. But, I don't think that simply making deliberate, informed choices about what and how to eat necessarily constitutes "moralism," across the board.
Example: Personally, I think that inhumane, drug-riddled industrial-style meat production is a bad thing for animals, consumers, and the entire eco-system. For myself, I try to find alternatives. I don't harangue diners at neighboring tables about it, I'm not tattooed with messages about it, I don't picket McDonald's. But it's a choice. I think it's a "moral" one, but not a "moralistic" one. (Just as eating kosher or halal may be a religious choice without necessarily being a narcissistic display of religiosity.) And the result, for me, is that I get more, not less pleasure out of eating.
"Strange how potent cheap music is."