A busload of demonstrators turned up at the Sydney outlet chanting "wake up" repeatedly, and brandishing placards bearing the same words.
Reports claim that the group was hired by Samsung as a publicity stunt to promote the release of its Galaxy S3 smartphone, which is expected to be officially unveiled next week.
Australian marketing blog Mumbrella traced the campaign back to a creative agency called Tongue, who run the 'Wake Up' website. Logging on to the site displays a countdown to 3pm on May 6, the Galaxy S3's rumored release date in the territory.
Samsung has poked fun at bitter rivals Apple in previous marketing campaigns. Last year, a Galaxy S2 video advertisement parodying the frenzied fan excitement around new Apple products became a viral hit on the internet.
The Galaxy S3, which will be powered by a quad-core processor chip, is widely expected to be unveiled at a launch event in London on May 3.