Breitbart News, an ultraconservative website that has served as a platform for the white nationalist “alt-right” movement, is touting its growing readership and “main street American values” as a reason advertisers should stick with it.

Some marketers, however, are heading for the exits, directing their advertising dollars away from Breitbart amid the publication’s call for a boycott against Kellogg’s (K), which has pulled its ads from the site. That prompted Breitbart to declare “war” on Kellogg’s: Editor-in-Chief Alexander Marlow said on the site that “to blacklist Breitbart News in order to placate left-wing totalitarians is a disgraceful act of cowardice.”

Breitbart’s campaign against Kellogg’s is unusual on a number of fronts, not in the least because news organizations traditionally maintain a separation between their business operations and their editors and reporters so that journalists can operate independently from business interests.

And whether the boycott will help Breitbart financially appears questionable, given that attacking a major advertiser isn’t likely to make the site more appealing to other brands.

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“Reporters don’t behave that way in the U.S., nor should they,” said Lee Wilkins, professor and chair of the department of communications at Wayne State University, who’s an expert in media ethics. “Most journalistic organizations have checks between the people who pay for your news work and the news work itself, so that you are as a journalist protected from those influences.”

She said she views Breitbart as a blog rather than a journalistic organization. “If you aren’t a journalism organization, then those safeguards are never in place.”

Other companies saying this week that they’ll pull their ads from Breitbart include Vanguard, 3M (MMM) and AARP, among others.

Kellogg’s said it decided to remove its advertising because Breitbart didn’t align with its values. It said the decision has “nothing to do with politics.” Stephen Bannon, Breitbart’s former chairman, served on President-elect Donald Trump’s campaign and is now set to become one of the incoming president’s top advisers in the White House.

Vanguard said it removed its ads as soon as it became aware that they were running on Breitbart. “As a policy, Vanguard does not advertise on any overtly political websites, including the site in question,” a spokeswoman wrote in an email. She said the ads appeared as part of a “remarketing” program, which are ads that appear to clients and investors when they visit third-party websites because of their browsing history.

“Our remarketing advertisements are limited to pre-approved sites (again, no political sites), however it was brought to our attention last week that this site was inadvertently included,” she said.

Breitbart’s advertiser showdown comes as the anti-Trump campaign #GrabYourWallet is taking aim at the site, officially adding it to its own boycott list on Thursday. #GrabYourWallet was created before the election by Sue Atencio, a 59-year-old grandmother, and marketing specialist Shannon Coulter, as a way to express concerns about Trump’s boasts of sexual assault. Since his victory, the boycott of stores that sell Trump brands has picked up steam.

“Because of the way digital advertising works, we’re not yet adding companies that advertise on Bretibart to the boycott list,” Coulter said. “We’re giving them time to work with their media buyers and ad networks to ensure their ads no longer appear there.”

While Breitbart is billing Kellogg’s decision as “bigoted and anti-American,” it’s a well-established American business practice for corporations to shift their sponsorship to companies they believe will help bolster their brand. In the case of reaching conservative audiences, advertisers that exit Breitbart aren’t necessarily snubbing those consumers because other conservative-leaning outlets, such as Fox News or Glenn Beck’s The Blaze, have an overlap.

“There are a lot of places advertisers can go to reach the same audience, and even maybe a bigger audience,” Wilkins said.

Nevertheless, Breitbart has been buidling its readership in the past year. Five Thirty Eight noted that its traffic has increased along with Trump’s political career. While many news sites got a bump in traffic as the campaign heated up, Breitbart’s growth was faster than other sites.

Some Breitbart readers are joining the boycott with enthusiasm, tweeting statements such as “cereal shouldn’t be political” with the hashtag #dumpkelloggs. At the same time, their message is generating pushback from internet wags who are creating satirical names under the hashtag #BreitbartCereals, such as “Race Krispies” and “Grope Nut Flakes.”

Breitbart is “behaving stupidly,” Wilkins said of the Kellogg’s boycott. “Unfortunately, we are all allowed to be stupid.”