Adams really means that certain McDonald’s menu items exist for reasons of rhetoric rather than gastronomy or sustenance. We don’t necessarily want to eat Big Macs or Apple Pies or Quarter Pounders, but we do want to consume the idea that we could eat them, even if we never intend to. In our age of wanton disruption and renewal, it turns out that we still pine for our cultural icons, even if not enough to enact earnest exaltation for them.

Today’s hip fast casual diner might occasionally slum it at a McDonald’s, sometimes for ironic reasons, but more often to dip a toe into the roaring river of cultural and personal memory. In a recent paean to McDo, Paul Smalera puts his finger on the matter:

I come not to praise McDonald’s, but not, exactly, to bury it either. As for every other American kid growing up in the ’80s and ’90s, McDonald’s was The Special Treat. Especially when the kid was under the age of, say, 10. In the mall (another dying institution), for being good during mom’s race through the department stores, coupons in hand, a Happy Meal. Thru the Drive-Thru, after school, when mom had to go to work the overnight data-processing shift, and hadn’t had time to make a meal for me and my dad, chicken nuggets. For dad, who would be on his way home from his 5am-4pm shift at the machine shop, a Big Mac, though he would complain that it was “too much.”

Smalera distinguishes the personal and the patriotic strains of McDonald’s cultural history. Just by being there—and by being the same everywhere—McDonald’s offered succor. This was, after all, the fundamental promise of the fast-food chain: cheap, accessible food that would always be the same anywhere. Even if we knew it wasn’t really food, exactly, sometimes convenience and comfort were more important. Particularly among the middle classes who were fortunate enough to appreciate McDo as the treat Smalera remembers, rather than as an affordable meal.

But with a Chipotle on every corner in gentrified America, practically, fast casual has become as convenient as fast food—perhaps even more convenient in the more affluent communities it targets. And so the Chipotle connoisseur darkens the drive-thru of a McDonald’s for comfort alone.

This isn’t a nostalgic or an ironic kind of comfort, even as it isn't one pursued for the sake of eating by oneself. When the modern, affluent customer makes an autumnal pilgrimage for a McRib or a vernal one for a Double Filet-O-Fish, he or she doesn't just do so for Instagram fodder. The McRib reveals the weird science of processed fast food so as to help us construe it as normal. And the Filet-O-Fish connects drive-thru hamburgerdom with the sacrificial demands of Lenten Catholicism. These are acts infused with ritual instead of cynicism.

But the McRib and the Filet-O-Fish are still curiosities compared to the Quarter Pounder and the Big Mac, two hamburgers at the heart of a beloved, if struggling, paradigm. These latter menu items aren’t ironic curiosities so much as the very meat of fast food fandom. And more than that, too, they're a metric for American economic might, by means of the so-called Big Mac Index, which The Economist has long used to compare the relative purchasing power of different currencies.