Meat wars: This is winning on fast food, fast casual menus

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As restaurants take advantage of National Cheeseburger Day to highlight burgers, a different meat is popping up more often on the menus of limited-service restaurants, which includes fast food and fast casual.

Recent additions, such as McDonald's premium buttermilk crispy chicken deluxe sandwich or Wendy's Asiago ranch chicken club, are just two examples of this phenomenon.

Shake Shack Roadside Shack burger, left, and a McDonald's premium buttermilk crispy chicken deluxe sandwich
Source: Shake Shack; McDonald's

Technomic data show the total number of chicken sandwich/wrap items rose 3.4 percent at these restaurants to 8,118 while burgers rose 1.3 percent to 7,182 during the second quarter, compared to the year-prior period.

Rachel Royster, senior coordinator of editorial content at Technomic, attributed chicken's higher growth to a "health halo" effect.

"People still want burgers. That's never going to end. They're willing to pay a premium for it. But we do see more interest in healthier items," Royster said.

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Diners are following suit and ordering more breaded chicken sandwiches, according to data from The NPD Group. They bought about 2.3 billion of those sandwiches in the year ended in July, up 3 percent compared to a year ago. (It's worth noting that this does not include all chicken sandwiches.) This compares to 7.09 billion cheeseburgers—a much larger number though it grew just 1 percent from the prior period.

Increased customization is another factor driving burgers' slower growth. Restaurants increasingly favor letting customers choose from a plethora of toppings rather than adding as many menu items.

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While limited-service restaurants are doubling down on adding chicken sandwiches to their menus, burgers are the standout winners when it comes to limited-time promotions chains use to get people in the door.

These restaurants debuted 112 burger limited-time offerings, such as Shake Shack's Roadside Shack burger or Fatburger's Western BBQ bacon Fatburger, for the year ended in August, versus just 54 for chicken.

What's behind the disparity between promotions and the full menu? One word: indulgence.

"There's definitely more indulgent offerings with burgers and when talking about LTOs, people get more excited about the indulgent offerings than the healthier ones," Royster said.