Researchers studying plain packaging for cigarettes have found smokers leave their packs with the brand logo facing up 80 percent of the time.
Nick Wilson from Otago University said medical students in Wellington observed nearly 20,000 people sitting at tables outside cafes and bars.
They spotted 17,000 packs of cigarettes, and found the vast majority of them had the brand name facing up and the graphic health warning facing down.
Mr Wilson said the study demonstrated how often cigarette packs act as a form of marketing.
He said Australian research has shown fewer smokers leave their packs on public display when plain packaging laws are introduced.