The conflict played out Friday night when a majority voted to stay in Dilworth and to offer nonviolent resistance training for those who wanted to remain.
City officials, who have struck a mostly conciliatory tone with the Occupy group, allowing several hundred of them to camp on Dilworth Plaza until construction begins, say they are growing more worried because the protesters have become less communicative.
"We're seeing a change in tone," said Richard Negrin, Philadelphia's managing director. "There seems to be a more radical element, and that's a concern for us. We started with great communication. We were talking regularly, and that has broken down to some extent."
Philadelphia is trying to avoid the kinds of confrontation that have led to violence at some Occupy sites, most notably in Oakland, Calif.
The Philadelphia group took to the streets Saturday and marched from City Hall to the Comcast Center at 17th Street and John F. Kennedy Boulevard to protest what they say is the company's failure to pay its "fair share" of local and state taxes and the pay of chairman and CEO Brian L. Roberts. One of the world's largest entertainment and media companies, Comcast is also a leading area employer. A Comcast spokesman declined to comment.
A handful of protesters moved toward the building to deliver a giant check but were met by a row of the civilian-dressed Philadelphia Police civil affairs unit.
The city has spent about $500,000 - mostly in police overtime - to monitor Occupy Philadelphia. There have been arrests only during two demonstrations - inside the Comcast tower and outside police headquarters.
Philadelphia has said the Occupy protesters could move to another site. When the Philly protest began in early October, the city issued a permit that said participants could stay on Dilworth until construction started, but no specific date was discussed.
The Dilworth overhaul includes remaking the underground SEPTA concourses, adding a fountain, lawn, trees, and a cafe with seating. In the winter, skaters could glide over a portable ice rink.
Some protesters have complained that the $50 million would be better spent to house and feed people. The city counters that Dilworth has been decaying for years and that the project will add green space and employ as many as 1,000 people over two years. Federal and state funds are paying for the construction.
Some participants have come to see staying at Dilworth as the only way to maintain leverage for their demands.
Michael Blas, 27, who is unemployed, said he believes that the group's stance at Dilworth has helped the homeless, establishing the right for them to stay there.
"I would hate for this to be a herding up of the homeless," he said.
Although city officials have suggested Occupiers could move just across the street to the plaza on the east side of the Municipal Services Building, Blas thinks that would be just the first in an endless series of moves for the homeless.
Nikki Allen Poe, 32, disagreed. He appreciates that the city has largely supported Occupiers and says the Dilworth project will give jobs to many of his union friends who are out of work.
"As a lifelong Philadelphian, I think that if you block a project like this, you are hurting jobs," he said.
Moving the encampment across the street makes sense and still provides the opportunity to take a stand, he said.
"If they try to move us from Municipal Plaza, I'll duct-tape myself to the Frank Rizzo statue," Poe said.
Blas and Poe argued vigorously, but they get along.
"We're good buddies," Blas said. "You are going to find people you disagree with in this movement."
Experts who study social movements say it is common for members to battle as they assess priorities.
"Especially as social movements expand, you often see these types of divisions taking place," said Catherine Wilson, a Villanova University political science professor. "So many different types of groups are trying to gain traction."
George Ciccariello-Maher, a professor of history and politics at Drexel University, said the Occupy movement was unusual because it contains people from across the political spectrum.
"The first thing that is peculiar about the Occupy movement as a whole is just how broad it is," he said. "It involves people from the right, the center, the left, and that can lead to different positions."
The disagreement over moving may reflect the varying experience of protesters, he said.
The city's generally cooperative stance may simply be a way to get protesters to leave peacefully, he added.
In various civil rights movements, protesters have succeeded by staying their ground.
"They refused to leave, they locked arms," he said.
Even though the Occupy movement nationally is aimed at diminishing social inequities, the local group has demanded that the city end its curfew policy and terminate relationships with certain banks.
If the protesters move, they lose power, Ciccariello-Maher said.
But, the protesters clearly don't speak with one voice.
Negrin said some protesters unhappy with Friday's vote had contacted him via phone and Twitter to express their disappointment that the group had decided to stay.
"Nothing has really changed in terms of official Occupy, but I think we are disappointed and concerned about the way things are going," he said.
The Occupy Philly factions have taken their battle to the Web. A group calling itself Reasonable Solutions has started a blog that supports the Dilworth renovation and calls for protesters to cooperate with the city and move.
Another group calling itself the Radical Caucus of Occupy Philadelphia has a Facebook page where it defines its goals as "to resist police eviction efforts, to put forward local demands, and to prepare to mobilize to enforce those demands."
Shawn McMonigle, 24, of Philadelphia, a participant, who voted to remain at Dilworth, said staying makes a statement, and he was willing to get arrested.
"This is an occupation and we're occupying for a reason. We're fighting for a better world," he said.
"If you think about history and the women's rights movement and the civil rights movement, those individuals didn't get permission to do what needed to be done to change the world."
Richard Newman, a professor who studies reform movements at Rochester Institute of Technology, said the debate reminded him of abolitionists who could not agree on whether to use the political system by backing candidates to promote their cause. Participants in the civil rights movement, too, were often divided over such issues as communism, he said.
"This is often the way that radicals within movements gain traction," he said. "You get your radical anarchists who join up with some frustrated moderates and then they realize that people are paying attention and now maybe the radical anarchist wants to push harder, and the moderate says, 'I'm not so sure.' "
Contact staff writer Miriam Hill at 215-854-5520, firstname.lastname@example.org, or @miriamhill on Twitter.
Staff writer Darran Simon contributed to this article.