Protesters have been calling for the manager's firing since two black men were arrested for trespassing last week while waiting on an acquaintance for a business meeting.
The chief executive officer of Starbucks is in Philadelphia to have a meeting with Mayor Jim Kenney and is hoping to deliver a face-to-face apology to the two men.
The second day of protests has kept the Starbucks store near Rittenhouse Square from opening to the public.
The protesters entered the store Monday morning and chanted, "Starbucks Coffee is anti-black."
"They will not make money at the Starbucks today. We will hit them where it hurts and that's in their pockets," Abdul-Ali Muhammad of the Black and Brown Workers Cooperative said.
For nearly five hours, over two dozen protesters filled the Starbucks expressing their outrage over Thursday's arrests.
Video of the incident has now racked up over 10 million views and prompted the demonstrations.
Protesters with the Black and Brown Workers Cooperative and Philly for Real Justice lined up outside of the store in the pouring rain beginning at 7 a.m.
Minutes later, they filed in.
The protest forced the store to shut down for the busy morning rush. Some customers got angry as they were turned away.
Though things remained peaceful, tempers flared and, at times, protesters directed their anger at employees, mostly from corporate.
Some hid, while others stood at a distance.
"We are here to tell you that that is not acceptable and ma'am since you want to know so much, what you are going to do is change those policies, what you are going to do is stop calling the police, because we are committed to being here are much as possible," one activist said.
On Monday morning, Starbucks CEO Kevin Johnson appeared on ABC's Good Morning America saying he was in Philly to offer the two men a face-to-face apology.
Johnson will meet with Mayor Kenney some time during the day to do damage control.
Meanwhile, speaking exclusively to 6abc Action News, Police Commissioner Richard Ross says he stands by the officers who made the arrest saying they were simply following procedure.
"Unless someone comes forward with something more than I know now, it doesn't appear that they did anything wrong at all. In fact, they were really trying not to make an arrest in this case," Ross said.
The demonstrations began around noon on Sunday when protesters showed up holding signs and shouting messages of anger outside the coffee shop.
Among the demonstrators was Melissa DePino who captured the video of the arrest being passed around on social media.
"There's nothing more to the story than what you see in the video," said DePino. "And when people say 'there must be more to the story' that's part of the problem in my view."
Leaders from several organizations attended Sunday's protest at the store, demanding that the manager be fired and thanking the customers in the store who interjected during the arrests.
"They spoke up for those two black men. They put their bodies on the line," said Asa Khalif. "They spoke up and they challenged the police and they filmed. This is what allies do."
The protest spilled into the store where Starbucks Regional Vice President Camille Hymes spoke to the crowd, addressing calls for the manager's firing.
"We take full responsibility and put her in a position that did not set her up for success or for those two men," said Hymes.
The incident sparked an internal investigation within the Philadelphia Police Department, leading the commissioner to release a statement last week:
"These officers did absolutely nothing wrong," said Philadelphia Police Commissioner Richard Ross. "They followed policy. They did what they were supposed to do."
It also led Starbucks CEO Kevin Johnson to release an apology, calling the arrest a "disheartening situation" that led to a "reprehensible outcome."
He said a company-wide meeting will be held this week to address the incident.
After their arrests, the two men were released early Friday morning.
The Philadelphia District Attorney declined to press charges because of a lack of evidence.