Starbucks workers at more than 150 stores launched a week-long strike, alleging that employees at dozens of U.S. locations were restricted or barred from putting up Pride decorations, a claim the company has denied.

Starbucks Workers United said the walkout involving more than 3,000 workers in at least 28 states began Friday at the company's flagship store in Seattle. Employees at other locations will strike throughout the week, affecting less than 2 percent of company-operated stores across the United States.

"Starbucks is scared of the power that their queer partners hold, and they should be," Moe Mills, a shift supervisor from Richmond Heights, Mo., said in a statement.

But company spokeswoman Rachel Wall accused the union of spreading false information, calling the strike a "tactic used to seemingly divide our partners" in an emailed statement to The Washington Post.

It's the latest culture war flare-up to play out in the workplace, as a range of companies come under scrutiny from workers and consumers alike over their perceived commitment, or lack thereof, to polarizing social issues.

Last week, the union accused regional-level Starbucks leaders and store managers of blocking workers from putting up Pride flags and other decor commemorating LGBTQ+ rights. The union cited statements by workers who claimed they had been prohibited or limited in putting up decorations, as well as texts and a memo referencing guidance from regional managers to ensure stores adhere to a more "consistent experience." The communications could not be independently verified by The Post.

The union says it is not alleging the actions were a result of a "corporate top-down national policy." Still, it's "very hard to believe that corporate was unaware" of the actions because the purported instances of it happening were so widespread, according to a statement to The Post.

"We find this weird restriction - or in some stores, downright refusal - to have Pride decorations to fly in the face of Starbucks values," Parker Anthony Davis, a 21-year-old barista in San Antonio, said.

"That is very concerning in this current climate - and it makes me worried," added Davis, who identifies as asexual. "I want to make sure that I am working for a company that is going to push these values forward and going to protect people that are simply human."

Davis said employees at his store did not run into any trouble putting up Pride decor, but he said it will probably strike on Thursday to stand with the stores that the union says had faced restrictions.

Starbucks has vehemently denied the allegations, pointing to decades of support to LGBTQ+ workers through policies such as "gender transition guidelines" and the addition of gender reassignment surgery to the company's health benefits. Moreover, Wall said that the company has long had a policy of empowering "partner celebrations and recognition of a variety of heritage months."

Asked whether the store managers and regional leaders could have been acting independently from corporate guidance, Wall responded: "As for in-store displays, partners and store leadership continue to find ways to authentically celebrate with their diverse communities year-round within our safety standards, signage policies and dress code."

"All reported partner concerns on this matter are being taken seriously and are routed for leadership review and to be addressed," she added.

The union alleges the decor episodes add to a list of retaliatory practices against staff, including blocking workers' access to benefits and the firing of a barista who had been leading a union drive at her store.

Starbucks and the workers fighting to unionize have been locked in a battle - one that pushed company founder and former chief executive Howard Schultz to testify about his company's alleged union busting before a congressional panel in March. Schultz denied being involved in any decisions to terminate or discipline union organizers and claimed he had not taken part in closing unionized stores.

That testimony came only weeks after a federal administrative law judge found that Starbucks committed "egregious and widespread" violations of federal labor law through efforts to halt union campaigns.

Starbucks, which employs 250,000 people in the United States and 450,000 worldwide, is one of the most recognizable brands in the world. It generated more than $32 billion in sales last year. Shares fell 2.5 percent Friday, giving it a market value of nearly $116 billion, according to MarketWatch.

In recent months, brands from Target to Anheuser-Busch have endured criticism in stores and online over polarizing social issues. Tension ramped up in April, when Anheuser-Busch faced criticism and boycotts over its Bud Light partnership with transgender actress Dylan Mulvaney. Retailers such as Kohl's, Walmart and PetSmart have also gotten criticism from the far right for stocking items that extol equal rights and acceptance for gay, lesbian and transgender individuals.

In late May during the lead-up to Pride month, Target pulled back some LGBTQ+ merchandise and promotional materials from storefronts, citing worries about worker safety.

Since then, stores in at least eight states have received bomb threats - no explosives were discovered. Though several were purportedly made by people claiming to be angry about the removal of Pride merchandise, this has not been verified by law enforcement.