A man, in gang regalia, and a woman were caught on video at Salt on The Pier in New Brighton walking away with a tip-jar containing between $100 and $150.
An empty tip-jar was later found in the lift outside the restaurant.
Owner-operator Sam Alla said this behaviour was typical of the New Brighton area.
"This behaviour is becoming more and more prominent around New Brighton unfortunately, we have a cafe downstairs and a lot of people steal ice creams from down there," he said.
"We caught someone once and they were really frustrated and said: 'Hey I'm not paying for this.' It is just very disappointing and frustrating behaviour to see around New Brighton."
Mr Alla said the CCTV footage has been passed on to police.
He said customers had since come into the restaurant to refill the tip-jar.
"Yesterday we had somebody come in and they knew about the video and they put $20 in."
A police spokeswoman said police would be making further inquiries around the matter.
She said thefts like these do happen from time to time in the area.
"While the amount of money lost may not be huge in the grand scheme of things, the incidents are nonetheless frustrating for our local hardworking people," she said.
