The runaway success of Popeyes Louisiana Kitchen’s chicken sandwich has encouraged the chain’s parent company to rethink how it promotes new menu items.

TV figured prominently in the original launch marketing plans for the Popeyes sandwich in August, with a commercial produced and ready for distribution, said Fernando Machado, global chief marketing officer for Burger King and Popeyes, which are owned by

Restaurant Brands International Inc.

But once a well-timed Popeyes tweet kicked off a so-called chicken sandwich war, the company decided to hold back its TV campaign to let the enthusiasm grow organically.

That tweet, in which Popeyes snarkily responded to a

Twitter

post by rival Chick-fil-A Inc. claiming its own sandwich was the “original,” has been retweeted more than 86,000 times.

The tactic, combined with related publicity and the appeal of the product itself, worked: Sales at comparable Popeyes restaurants grew 10.2% in the U.S. during the third quarter, largely driven by the furor over the chicken sandwich, which sold out in roughly two weeks.

When Popeyes decided to bring the sandwich back in October, the company again decided to forego TV advertising and committed all of its paid media to digital and social media, print and out-of-home advertising.

“It was all to drive talkability on social and get coverage through PR,” said Mr. Machado. “Normally we do a lot of TV, a little bit of digital, and really push on launch—here we have the most successful product launch since I started here six years ago, and it involved zero TV advertising.”

“It was an unusual approach for us, which will help shape other launches in the future,” he added.

Broader shift

Popeyes and Burger King have both been edging toward spending more on digital media as their investment in tech products and services, including mobile ordering and delivery, has grown. It is easier to get users to download and use an app through digital advertising and promotions than by using TV commercials, while younger consumers’ dwindling TV time and rising use of other screens has also driven investment, Mr. Machado said.

But TV still typically reaps about 80% to 90% of Burger King and Popeyes’ global media budget, especially during new product launches, when the goal is to get the message out as far and as wide as possible.

That is typical for fast-food marketing, Mr. Machado said. “It’s a very retail type of category; you are constantly reminded of the brands, the offers, the promotions,” he said.

Burger King and Popeyes devote a smaller share of ad spending to digital in the U.S. than in some other markets, Mr. Machado said.

And TV will remain a big part of the company’s marketing plans, he said. “It’s still a very effective way to get the word out and get massive reach, though this launch breaks the thought that you can’t launch without TV,” he said.

But he hopes to boost digital ad spending to as much as 20% to 30% of the overall media budget within the next few years.

Mr. Machado declined to comment on how much Popeyes spent promoting its new chicken sandwich, but said the company didn’t spend less by skipping TV.

“Sometimes people have the misconception that a digital campaign should be cheaper than a TV one. The reality is that if you want to trigger talkability in social media, you need to invest properly behind the idea,” he said.

Digital lag

“Restaurants brands at large have been behind other verticals in digital because restaurant sales have moved online more slowly than sales in categories like electronics and apparel,” said William Duffy, a research director at Gartner Inc.

“But with couriers surging in usage and leading brands reporting strong digital growth, restaurant brands are recognizing digital as an opportunity and a threat, and many are now focusing on improving their native digital fulfillment options,” he added.

The RBI brands have been known to create interest using digital marketing stunts. Last year, Burger King ran a promotion on its app which offered customers a Whopper for 1 cent if they went near a

McDonald’s

location. The campaign helped drive 1 million downloads of Burger King’s updated app in October 2018.

“They do a great job with buzzy campaigns,” Mr. Duffy said of Burger King. The goal for marketers is to translate any excitement they generate into repeat customers.

With Popeyes, the chicken sandwich craze was fueled by conversations on Twitter. Tweets about the Popeyes brand rose to about 4,000 a day—twice the regular volume, year over year—in the first week after the sandwich’s launch on August 12, said God-is Rivera, global director of culture and community on Twitter.

One of the most active pro-Popeyes groups on Twitter was what some refer to as “Black Twitter,” where people were talking about the sandwich even before the sandwich wars, Ms. Rivera said. She noted that the buzz wasn’t just coming from stars with large follower-counts, in what could be a sign that it is getting easier for regular social-media users to influence the conversation around a brand.

Write to Sahil Patel at sahil.patel@wsj.com

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