Labor organizers representing employees from blue-chip firms such as outdoors retailer REI and animation studio Titmouse also attended the meeting with Biden.
Vice President Kamala Harris and Labor Secretary Marty Walsh convened the meeting, but Biden dropped in unannounced a short time later, according to the White House.
Starbucks, which is now led by interim CEO Howard Schultz, has been fiercely opposed to efforts by its employees to unionize.
In a letter to a top Biden adviser, Starbucks PR chief A.J. Jones slammed the White House for its “lack of representation” and noted that “a majority of our partners (employees) oppose being members of a union and the unionization tactics being deployed by Workers United.”
“We have a drastically more positive vision for our partners and our company than Workers United,” Jones wrote.
“And our vision is based on listening, connecting, collaborating and engaging directly with our partners.”
Jones lobbied the White House to invite other Starbucks employees who oppose the organized labor drive, which has so far resulted in successful unionization votes at 50 different locations nationwide.
An estimated 200 other Starbucks restaurants are due to either hold unionization votes or to hear the votes counted.
Earlier this week, Schultz announced expanded wages and benefits for baristas, including higher hourly pay and increased training, though those perks would not be extended to employees who join unions.
Starbucks Workers United Organizing Committee told CNBC: “These benefits, including ones we’ve demanded since the beginning of our campaign, are a response to our organizing efforts and we should celebrate the hard work that partners who stood up to [CEO] Howard Schultz’s bullying put in to make this happen.
“Many of the proposed benefits have been proposed at the bargaining table in Buffalo.”
Schultz and other top Starbucks executives have accused pro-union baristas of using strong-arm tactics such as bullying and intimidating colleagues to support the labor drive. Labor organizers deny this, instead accusing the company of illegal union-busting.
According to the pro-labor news site More Perfect Union, Starbucks Workers United has filed more than 80 unfair labor practice complaints against the company.
Starbucks, which owns and operates some 9,000 locations across the United States, has been accused of firing pro-union baristas and reprimanding other workers who have also been active in the organized labor drive.