In 2018, the company's total ad revenue grew 38% to $55 billion, the company said on its fourth-quarter earnings call, and net digital ad revenue in the U.S. grew 36% to $23.66 billion, according to Feb. 2019 data from eMarketer.
The company's share of ad revenue is growing, too. Facebook's net digital ad revenue share in the U.S. grew from 19.8% in 2017 to 21.8% in 2018, and was expected to reach 22.9% by 2021. Meanwhile, Google's net digital ad revenue share in the U.S. shrank from 39.6% in 2017 to 38.2% in 2018, according to eMarketer.
Advertisers keep spending because, despite all the negative publicity and calls to boycott the service, users are sticking around: Facebook's monthly active users grew 9 percent to 2.32 billion in 2018.
With Facebook's level of reach, "It just makes sense to always recommend that to our clients," says Shuman Sahu, director of performance media at performance digital marketing agency Nina Hale. "We definitely don't exclude Facebook because of the scrutiny they've gone through."
Tom Buontempo, president of social media agency Attention, says any outrage around Facebook's scandals has been short-lived. If anything, brands are often spending more on Facebook, he said.
"More of our clients are spending more across the Facebook ecosystem," he says. "There aren't a lot of options right now." He says it's tough for brands to get the same kind of return for their money as they do on Facebook. And though Amazon has emerged as a big contender, it hasn't stung the Facebook ecosystem in terms of spend, he said.
GroupM's global president of business intelligence Brian Wieser says it would take a brand believing their reputation could be hurt to make meaningful changes.
"The real thing that would cause a brand to slow spending is if they thought their brand would be tarnished," he said.
That's a lot less likely to happen with Facebook than with Google's YouTube, for example, where a brand's ad could appear directly on a video containing disturbing content. For Facebook, any issues "don't stick to the brands — yet," he said.
"Individual advertisers can be concerned about all of these things and they're very alert to these things now in ways they weren't two years ago -- that doesn't mean they're changing what they're doing," he said. "They're just very, very aware and very mindful that things could get much worse for them in terms of their association."