The Scottish chef said he has been left “shellshocked” by today’s decision which will involve all such premises closing in the Greater Glasgow and Clyde, Lanarkshire, Forth Valley, Lothian and Ayrshire and Arran health board areas - affecting about 3.4 million people - from 6pm on Friday until October 25.
In other parts of Scotland, pubs and restaurants will be open from 6am to 6pm but can only serve alcohol outdoors until 10pm.
First Minister Nicola Sturgeon said the evidence paper published on Wednesday pointed to the R number appearing to rise above one about three weeks after the hospitality sector reopened, and that more than a fifth of people contacted by test and trace reported visiting a hospitality setting.
Speaking to The Scotsman tonight, Mr Nairn said: “We did not realise pretty much 100 percent of the blame would be on hospitality in the central belt and involve shutting everything down and we’re still shellshocked by that decision.
“Something doesn’t add up. Nicola Sturgeon said 20 percent of all people with covid have been in a hospitality setting - but maybe all of them have been to a shop or in contact with someone in educational settings, and some will have been on public transport. It’s a nonsense statistic.
“We need better science and really need to know who is responsible (for transmission).”
Mr Nairn also said the £40 million support package offered to affected businesses will not go nearly far enough because, even if it helps with employer contributions to staff furlough wages, there are still many other costs such as rent, insurance and the food which will perish due to the impending closures.
He is particularly frustrated given that pubs and restaurant owners have been working extremely hard to stick to protocols around hygiene and social distancing and recording contact details given they are under public scrutiny.
The chef, who opened a new restaurant in Bridge of Allan with his wife Julia at the start of the year, also says he can not fathom why restaurants and pubs have been grouped together, particularly as his restaurant is family friendly and staff adhere to government guidelines.
And he believes more people might now choose to breach other rules by visiting different households instead of going to pubs or restaurants.
Mr Nairn also said that he has been receiving several queries for restaurant bookings on October 26 but he can not take these as it is not completely clear if they will be able to reopen on this date, fuelling more uncertainty.
He added: “We are at our wits end and have done everything possible to get it safe. I totally agree that we have to do something but why hospitality?”
“There will be a lot of business owners who are already beleaguered and, when they wake up in the morning, might be thinking ‘is the game worth the candle?’ It’s a huge blow.”