One thing I've also noticed is that people who grow up in traditionally religious households but reject religion as adults very often sublimate their religious dietary practices into quasi-religious food behaviors: you take someone who grew up in a kosher household but no longer observes the laws of kashruth and I can guarantee you that person has a significantly higher percentage chance than the general population of subscribing to one or another variety of rigorous dietary regimen.

I would suspect quite the opposite to be true. If I had had such tight restrictions in my youth, I would opt for the most *trefah and permissable of options ...Ham and oysters and all types of shrimp .. cheeseburgers, etc. all of which I had missed in my upbringing.
but I may be completely off-base in my assumptions ...
* Forbidden food is called trefah

I was raised fundamentalist Protestant in the Jell-O salad South--at Bob Jones University, no less--and I make my living from being a no-holds-barred hedonist. Maybe that's what not being allowed to wear jeans, watch TV, or go to the movies until I was 18 will do.
I'm in the middle of Jeremy Iggers' "The Garden of Eating: Food, Sex, and the Hunger for Meaning." I don't agree with all of his arguments, but he has some interesting analyses of the way sexual repression has been replaced by food anxiety, drawing a correlation between the sexual revolution and the post-Julia Child foodie revolution: "Child offered us a bite of tarte Tatin and...we looked at our Jell-O molds, tuna casseroles, and Hostess Twinkies and recoiled in shame."
He cites a study that single women today feel less guilt about sleeping with a married man than they do about being seduced by Haagen-Dazs, and he points out that "sinful" these days is most often used to refer to dessert. Maybe it would be more accurate to say that food rather than religion has become the central battleground of personal moral conflict. Look at all the wrangling about dietary evils (salt, cholesterol, fat, MSG, Jell-O, carbs) and the politics.
When it comes to both religious and gastronomic dogma, I'm an avowed agnostic. I've always questioned authority--my sanity would not have survived otherwise. Take, for example, farmed vs. wild salmon. Yes, most salmon farms are horribly crowded and pose serious environmental problems--well documented elsewhere. However, I don't think domesticated salmon have to be so different from domesticated chicken. I visited a salmon farm in Norway last month, and it looked just like my uncle's Tyson-like chicken farm in Japan. I even tasted some of the fish food. It tasted like bonito flakes.
But why couldn't a premium farm-raised salmon--less crowded, raised on natural feed--not be the gastronomic equivalent of a Bresse chicken? People don't think wild turkey is automatically better than domestic--in fact, most people have to learn to like the taste of wild game. In May, I was served a wild salmon from the Loire at L'Ambroisie. (Important note: we did not order the salmon since it was not on the menu--the restaurant had only the one. The chef thought it would please us.) It was a very curious fish--very pale, even for a wild salmon, almost a ghost of a salmon. I was interested in having the new experience and it was of course perfectly prepared, but I could not say it was the best salmon I ever had. The fish had swum many, many miles more than other salmon and was at the last extremes of exhaustion, not to mention lean and delicate. I could also have said flabby and tasteless and still be right. Honestly, there is also something to be said for a fat fish custom fed for full flavor and harvested in the prime of life.
However, taste aside, was it right to eat something so rare? Did it have a chance to spawn after going so far? I have a friend who does not consider a 3-star experience good unless it features something rare. Is depleting the already perilous wild stock even further better for the environment?
I eat anything as long as my own moral conscience allows, and I think that's par for the course in modern smorgasbord Western ethics in general. Foie gras yes, beluga not any more.
As for foam eaters, I've often been called a food snob for my more extravagant flings and championing of modern foods. However, I do think there are at least two kinds of foodies: those that eat for pleasure, and those that eat for status. Iggers points out (not entirely accurately) that once everybody in America ate pretty much the same thing, but after the foodie revolution, there grew a class divide between those that still eat Jell-O and those who have recoiled in shame.
Frankly, life is too short for pointless shame. Eat what gives you joy is my personal creedo.