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One much-discussed trend in fast food is the push for healthier, lower-calorie options. The most recent examples include Burger King’s introduction of “Satisfries,” which the company claims have 40% less fat and 30% fewer calories than BK’s standard french fries, and McDonald’s decision to let customers choose a salad, fruit, or veggies as an alternative to the usual french fries that come with value meals. At the same time fast food giants are taking baby steps in the fight against obesity.

But another industry trend is heading in the exact opposite direction: the expansion of special menus that are both heavy on indulgent, fatty snacks, and featured during gluttony-prone, late-night hours.

The most striking example is a Munchie Meal offer from Jack in the Box. Starting at 9 p.m., the chain is selling a $6 combo meal with a regular (20 oz.) soda, “halfsie” fries (mix of curly and regular fries), and a choice of mad-scientist, over-the-top entrees including the Exploding Cheesy Chicken Sandwich (made with mozzarella cheese sticks and “gooey white cheese sauce”), the Brunch Burger (a fried egg and hash brown patty on top of the meat, described as perfect “when it’s so late you don’t know whether it’s dinner or breakfast”), and another burger capped with a grilled cheese sandwich. “It’s everything in moderation, but it appeals to a certain Millennial,” Jack in the Box spokesperson Jennifer Kennedy said to Nation’s Restaurant News of the new Munchie Meals. “They’re looking for an indulgent treat.”

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Robyn Flipse, a dietician, agreed that Jack in the Box’s new offer is clearly aimed at millennials. But as she told USA Today, she’s appalled at the notion of targeting consumers who are likely in “an altered state of mind,” and who otherwise probably would know better. “They are a disaster,” Flipse said of the Munchie Meal selections. “They must have hired some very stoned Millennials to dream this stuff up.” To complete the party scene, Jack in the Box is filling the late-night 9-5 shift with dance and Top 40 music played more loudly than during normal hours.

Jack in the Box may have rolled out the boldest appeal to the late-night munchies crowd, but it’s hardly the only chain restaurant wooing diners in the wee hours. Indeed, Jack in the Box launched its new options as a way to better compete with fast-food establishments already hot on the trail of young consumers who are awake, bored, and maybe not thinking so straight.

Denny’s “All Nighter” menu was introduced a few years ago with special $2.99 orders of nachos, pancakes, and such to firm up the chain’s reputation as an “after-hours hangout for bands and young adults.” Taco Bell may have been ridiculed for enticing people living in a country with an obesity problem to squeeze in an extra meal daily, but its “fourth meal” campaign is still alive and kicking. White Castle, famed for its late-night stoner clientele, has been testing the addition of breakfast after midnight to its 24/7 business model. Last year, the Wall Street Journal reported that the fastest-growing period for McDonald’s sales was the midnight-to-5 a.m. window, and that Dunkin’ Donuts had doubled its number of locations open 24 hours over the prior decade.

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In May, Wendy’s unearthed a late-night meal for $5, available only after 10 p.m. Over the summer, McDonald’s started offering breakfast items from midnight to 4 a.m., and began testing an After Midnight value menu. Hooters recently began a play for “night owls” as well, with half-price appetizers after 10 p.m.

To some extent, the longer hours and late-night menu specials increasingly available at franchise restaurants are a response to the changing workplace, in which more and more Americans are working night shifts and other odd hours. It makes sense for workers to be in the mood to grab a fast meal after punching the clock, no matter if that happens at 5 p.m. or 3 a.m. But a meal featuring deep-fried mozzarella sticks shoved on top of a chicken sandwich, all smothered in more gooey cheese? That probably only makes sense if you’re in a very specific frame of mind.