Beppi's, in Darlinghurst, NSW, had been expecting the party of six and when they failed to turn up they called the number provided.
However, the number went to voicemail.
With only ten diners allowed in Beppi's at a time, the customers' actions caused them to lose 60% of their revenue that evening, a post on the eatery's Facebook page said.
The restaurant branded the diners' behaviour as 'disgraceful.'
'It has been great to hear the sounds of diners back in our restaurant,' the post read.
'One disappointment has been the few customers that book and do not show up. Last night we had a total of table of 6 did not show. 60% of our revenue GONE.
'No call to cancel, phone just goes to message bank. Disgraceful behaviour.
We are temped to post the name and number of the customer however thought best not.'
The restaurant explained that they had decided not take credit card details along with bookings as they wanted to show their trust in their customers.
Fans of the restaurant were outraged about the incident.
'Absolutely disgusting behaviour!' commented one. 'I believe it is our duty to support local businesses. Particularly those so hard hit by the pandemic like Beppi’s.'
Another said, 'Name and shame, in these times it’s not appropriate to no show!'
From June 1, up to 50 people will be allowed to dine in restaurants in NSW depending on the premises' size.