About a third of Americans would be put off dining in a restaurant if a vaccine mandate was in force.
But an equal proportion would be more likely to dine indoors with such a mandate in place, a survey found.
New York City and San Francisco are mandating vaccines for indoor dining.
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One in three Americans say they'd be less likely to dine in a restaurant if they were forced to prove they'd been vaccinated, according to a survey by the National Restaurant Association.
The same proportion - 32% - said they'd be deterred from restaurant dining if they had to a wear masks, the survey, published Tuesday, showed.
However, 33% said that a vaccine mandate would actually make them more likely to dine in a restaurant. Meanwhile, 25% said a mask mandate would make them more likely to eat indoors.
New York City, San Francisco, New Orleans, and Los Angeles are among the cities that have already introduced or are considering introducing vaccine mandates for activities like indoor dining.
An analysis published in Nature found that the majority of COVID-19 infections early in the pandemic could be traced to "superspreader" locations, which included restaurants.
According to the National Restaurant Association survey, 35% of Americans say that a vaccine mandate wouldn't impact their restaurant use either way. The poll of 1,000 adults was conducted in mid-August.
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Restaurants fear backlash over vaccine and mask mandates
Some restaurant owners are worried that a vaccine mandate could lead to a drop in business from people who either aren't vaccinated or don't want to share their vaccination status. Just over a quarter of US adults haven't received their first vaccine yet, according to the CDC.
Art Depole, the owner of the Mooyah Burgers, Fries, and Shakes restaurant in Times Square, told Insider that New York City's vaccine mandate was deterring visitors from his restaurant. Business fell by up to 25% the week the city introduced its mandate, he said.
This loss in business could cause his restaurant to raise prices, Depole said. He said that around 20% of his staff planned to resign over the policy, too.
Depole said he understood the reasoning behind the vaccine mandate, but that the restaurant industry was "the easy target" and being "unfairly picked on."
Restaurants that voluntarily enforced their own vaccine mandates told Insider that some customers had left bad reviews and threatened to spit on and cough at staff over the policy.
Like the vaccine mandate, the mask mandate faced some public backlash when it was introduced, and some retail and hospitality workers said they were subjected to violence and harassment when asking customers to mask up. One 19-year-old McDonald's worker told Insider she was assaulted after asking a customer to wear a mask.
People's dining habits are changing as the Delta variant spreads across the US. Sixty percent of adults said they'd changed their restaurant use due to the rise in the Delta variant, with more people choosing to dine outdoors or shun restaurants altogether, per the National Restaurant Association survey.
This comes as restaurants continue to be hit by both labor and supply shortages, causing some to raise prices or slash opening hours. Three in four restaurant owners told the National Restaurant Association that recruiting and retaining employees was their top challenge in July. In January, this was just 8%.