CHICAGO — There is a battle for restaurant lunch visits between casual-dining restaurants and quick-service restaurants (QSRs), and the weapon of choice between these contenders is America’s all-time favorite restaurant food, burgers, reported The NPD Group.

Burgers have helped casual dining restaurants increase lunch visits by closing the price gap with quick service restaurants, according to NPD’s Checkout Tracking, which provides omnichannel receipt-based information from the same consumers over time.

The burger, which has racked up 8.9 billion servings ordered at restaurants and foodservice outlets as of year ending June 2015, can meet a wide variety of restaurant customers’ needs from simple and classic to high-end gourmet with a little dressing down or up. Its perennial popularity, affordability, flexibility and ability to provide a beef menu item while offsetting higher beef costs are among the reasons why this utility food has become the heavy artillery in the battle for lunch visits.

For casual dining restaurants, burgers have been able to level the playing field with quick service restaurants on price. For example, the average price of a burger at casual dining is $9.02 and is $5.62 at fast casual; however, the gap closes when considering that fries typically come with a burger order at casual dining restaurants and need to be purchased separately at fast casual restaurants. The price of adding fries at a fast casual concept slaps on an average of $2.89 to the check, based on NPD’s Checkout Tracking research.

Also compensating for the slightly higher burger price at casual dining restaurants is that consumers are factoring in the value of a full service sit down lunch meal.

Burger servings ordered at casual dining restaurants were up 3% in the year ending June 2015 period compared to year ago, and were the segment’s only menu category to grow in servings. In contrast, burgers servings ordered at quick service restaurants were flat, reports NPD’s ongoing foodservice market research, CREST.

The burger military offensive did, in fact, help casual-dining restaurants gain lunch traffic ground in the year ending June 2015 period. Lunch visits to casual dining restaurants increased by 2% in the period, the segment’s first traffic increase at lunch in five years, based on NPD’s CREST foodservice market research. QSR lunch visits increased by 1% in the period compared to year ago.

“It is an effective strategy on the part of casual dining and other full service restaurants to menu more burger items,” said Bonnie Riggs, NPD restaurant industry analyst. “Successful casual dining operators offer burgers that meet the tastes of their customers and are priced competitively. As a result, they gain lunch visitors.”

The NPD Group, Chicago, provides global information and advisory services. Sectors covered include automotive, beauty, consumer electronics, entertainment, fashion, food / foodservice, home, luxury, mobile, office supplies, sports, technology, toys and video games.