"It makes the whole night what it's supposed to be," said owner D'arcy Drollinger.
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They had been closed since the pandemic began, only reopening in June.
At the time, they were one of the first small venues in the city to require proof of vaccination, but got rid of the policy when things were looking good in early July.
"But as soon as the Delta variant was becoming more prevalent, for the safety of our patrons, our staff and our performers, it was the right thing to do," to reinstate the policy, he said.
Generally, he said feedback has been positive, though it has caused some confusion in line as customers fumble through their phones searching for a photo of their vaccine card or their record on the state website.
Drag performer Katya Smirnoff-Skyy says the comeback of their entire industry will rely on people feeling comfortable.
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"I think there is a lot of trepidation to coming back to live venues," she said.
In addition to calming patrons, the requirement could have another side effect.
"If you do really want to see this show it gives you some incentive to go and do the right thing for community at large."
At Vesuvio Cafe in North Beach, the policy has been in effect for a week, catching some off guard.
"I have it, but don't have it with me," said LJ Jones as she tried to make her way inside.
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Instead, she was allowed to sit outside, but felt frustrated by the policy.
"I won't come back here," she said.
For Haley Cruz, she came specifically because of the policy.
"Makes me feel safer as a customer," she said.
She hopes more bars follow suit, and it's possible they will.
The SF Bar Owners Alliance, a group of some 300 bars, plans to announce on Monday whether their members will make this a widespread policy at their locations.
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