Bar 44, which operates four locations, said that 3,200 people had cancelled December bookings.
Natalie Isaac, the operations director of the organization, stated that only a few people would have cancelled their flights before the pandemic.
Others claim that, even though they don't have to follow any new rules, the public is cautioning them and causing a drop in footfall and a loss in trade.
The Confederation of British Industry (CBI), has asked the government for financial support for affected businesses, but the Treasury has yet to reveal any new measures.
"People are concerned"
Bar 44, which operates restaurants in Bristol, Cardiff and London, claims that 1,000 of the 3200 cancelled bookings were due to the knock-on effects from Tom Jones's cancellations and the Stereophonics.
Ms Isaac stated that "Having to keep open, but not getting the business, is our biggest worry."
"This should have been our bumper two weeks prior to Christmas, but the calendar is worryingly empty. We are severely impacted, and without furlough, our staff won't have the ability to protect themselves."
Ms Isaac could not give an estimate of the trade loss for the month because the venues aren't operating at their full pre-pandemic capacity.
Due to staff shortages, they have been closing only five days per week.
"We are slowly refilling with small groups but people are concerned to go out again because they don't want Covid during Christmas."
"People don't realize the consequences of cancellations."
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According to the CBI, hospitality shops and businesses were facing a "double whammy": a collapsed demand and no financial assistance due to the government's Plan B. This Plan B was designed to stop the spread of Omicron variant.
Tony Danker, CBI director general, stated that the restrictions were balanced but ministers should clarify that they are temporary.
He said that while there are measures to keep the economy open and messages that encourage it, they have led to the closure of much of the economy.
"We saved these businesses over the past 18 months. He said that they kept them growing."
"We cannot lose that now to essentially, if unintentionally shut down the restaurant sector at any time of the year. He said that this was a significant cashflow loss.
We need to reexamine cashflow measures to help those businesses. When demand is so low for reasons that are understandable, we can't pretend the economy remains open. A Treasury spokesperson stated that the government had "acted quickly" to stop the spread of the virus while also "avoiding economic and social restrictions by allowing business to continue to operate".
"To protect the NHS and ensure that everyone is eligible receives their booster jabs quickly, it is our priority to do so.
The spokesperson said that the support package for PS400bn Covid-19 businesses will continue to be available through spring next year, and that the company will continue to respond appropriately to the evolving path of the virus as it has done since the outbreak.
"Partial lockdown" without support
Clive Watson, the boss of City Pub Group, stated that every type of booking has declined since the Plan B announcement.
He explained that "in a nutshell, big corporate parties have really begun to be cancelled which were really lucrative."
"To some extent, these were being compensated with smaller groups still booking, however, they're now starting to cancel aswell.
"What we are facing is a partial lockdown but no government assistance at this time."
Watson stated that it was worth keeping the doors open. However, he added that the impact of corporate events is now "next-to-none". Marc Hornby, founder of Caviar and Chips catering and hotel group, said that corporate event inquiries are now "next–to none".
Due to the current restrictions, the country-wide firm of external caterers based in Birmingham had to shift its focus to wedding events in 2022 and 2023.
"It's been an important drop - we are seeing 25% of what we'd normally see," Mr Hornby stated to the BBC.
"The greatest challenge has been the mixed messages and the government not realising the cost of cancelling events.
Although recruitment was difficult for 18 months, Mr Hornby stated that they had prepared more events and had already anticipated new restrictions.
The group also owns a pub located in Kenilworth that was opened in March 2020, one week before lockdown. It was converted to take-out during lockdown and reopened. However, there have been very few corporate bookings.
Christmas trading 'destroyed’Emma McClarkin is the chief executive of British Beer & Pub Association. She stated that Plan B restrictions had "destroyed the critical Christmas trading period for pubs."
She explained that further restrictions, such as a limit on the size of groups or closing down pubs, could be catastrophic.
"Pubs will need every trade they can get to survive the winter months ahead.
"Without it they will need a complete financial package from government, including support for VAT, business rates, and return of local authority grants.
"The chancellor must come to our aid once again."
Mitchells & Butlers, a restaurant operator that owns brands like O'Neill's Harvester, All Bar One, Toby Carvery and Harvester, spoke out saying: "We are deeply dissatisfied by the announcement about Plan B and its knock-on effects on our industry as it continues to rebuild our businesses during this pandemic.
"We will comply with Plan B regulations. The Covid pass provisions will not affect our businesses, and no face masks will be required in our restaurants and pubs.
"We do not plan to introduce additional restrictions, unless it is absolutely necessary."