"She complied with you. She gave you what you wanted and yet you still decided to take that young lady's life. Why?" said one man who asked to remain anonymous.
Christine Lugo, 40, was killed as she opened up shop.
Police said even after giving in to the suspect's demand for cash, the mother, daughter, and grandmother was shot anyway.
"It's senseless. It don't make no sense, the things that are going on out there is crazy," the man said.
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For the man, who asked we not share his name given his line of work, it's a tragedy he feels he may have been able to prevent.
Why? For more than a decade he's worked in security, most recently armed.
It's his belief he would have been a deterrent.
"I've dealt with a lot, I've seen a lot in this field," he said.
He's not alone.
"A lot of these stores need to step their game up and start hiring armed security because Philadelphia - it seems like it used to be 'Brotherly Love' but it's not 'Brotherly Love' no more," said Strike Force Protection Agency guard Howard Sanchez.
Sanchez said he wants to be the one to protect the Dunkin' when and if it reopens.
It's not about a paycheck for him. His son, who knew Lugo, also works here.
"When he called me he was crying, like he couldn't stop crying, like 'why her, why her?'" he said.
On Monday, Mayor Jim Kenney also addressed the killing and violence that continues plaguing the city.
"There's too quick access to guns in the country and in this state," Kenney said.
Kenney said strategies to address gun violence are changing in the post-pandemic era.
RELATED: City of Philadelphia giving out grants to stop gun violence
But some security experts believe, for the time being, they may be the best solution.
"Had this Dunkin' Donuts had armed security at the hour when this robbery occurred, it would have been prevented," said PA Task Force guard Darryl Richardson.
Community members have started handing out flyers hoping they can identify Lugo's killer.
Anyone with information is asked to call police.