That perimeter was so tight, that it even disrupted the seniors' regular meal delivery service.
"So I said, we've got a kitchen. We'll take care of it," said Chef Kathy Fang.
Fang runs Fang Restaurant - a popular eatery nearby.
She said when she heard what was going on, she felt obligated to help - delivering more than 150 meals on Thursday.
VIDEO: SF Chinatown's leaders expect tourism boost during APEC summit despite tight security
APEC summit to boost SF Chinatown tourism despite tight security
"I immediately thought of my grandparents. And I'm thinking, all these elderly people in there, they're other people's grandparents, they're other people's parents," Fang said.
But even outside of the perimeter, daily life has been impacted for countless people around San Francisco.
That includes in Chinatown - a neighborhood that was hoping to get one of the biggest boosts from APEC.
At the Golden Gate Fortune Cookie Factory, owner Kevin Chan says business has been significantly down.
"The traffic cannot cross Market Street. And the locals don't want to go out, and the tourists can't come in," Fang said.
It's a similar story at other places around Chinatown too, where streets have been noticeably empty in recent days.
VIDEO: SF leaders, community groups glam up city to wow visitors for APEC summit
SF glams up city to wow visitors for APEC summit
Steven Lee owns several businesses in the area.
On Thursday night, he hosted a walking tour of several historic bars and lounges in the neighborhood.
He said with most of the major APEC events now wrapping up, he hopes the city's international visitors will now have more time to explore parts of San Francisco.
"Thursday, Friday, Saturday should be really busy for all our businesses. We're crossing our fingers," said Lee.
Until that time comes though, Chan is encouraging locals to remember to stop by their favorite spots too.
"They should come to support. Not just APEC, but local business, mom and pop stores," he said.
RELATED APEC STORIES & VIDEOS:
- 2023 APEC summit: Everything to know about San Francisco road closures, security and more
- Day-by-day timeline of APEC Summit in San Francisco
- Watch ABC7's live coverage of APEC summit in San Francisco
- Biden, Xi emerge from hours of talks, agree to curb illicit fentanyl, restart military dialogue
- Around 80 protesters arrested after abandoning cars, blocking westbound Bay Bridge, CHP says
- Pres. Biden hosts APEC dinner with delegation heads at SF's Legion of Honor
- Here's where APEC protests are happening in SF with more expected
- The hottest event in SF: APEC gala with Pres. Biden, world leaders with performance by Gwen Stefani
- Opposing groups clash at SFO before President Xi's arrival
- Lush, private Bay Area estate is site for Xi-Biden meeting
- 'Stop Bombing Children': Israel-Gaza cease fire message projected on SF's Ferry Building
- Ferris wheel and laser beams now on in SF but city's APEC treatment getting mixed reviews
- 'Where are the people?': Some SF restaurants feeling the impact of APEC
- Aerial performance artists scale San Francisco's Transamerica Pyramid kicking off APEC
- SF leaders, community groups glam up city to wow visitors for APEC summit
- Yellen says her talks with Chinese finance chief laid groundwork for Biden's meeting with Xi