Edinburgh police have had to marshal hundreds of cars and pedestrians to prevent a third day of traffic chaos at a newly opened Krispy Kreme doughnut store in the city.

Seventy-two hours after the US chain's first Scottish outlet opened, drivers were still queueing for up to an hour to get their fill on Friday. The day before Lothian and Borders police urged motorists to avoid the western side of Edinburgh altogether due to the chaos. Patrol cars were sent to Hermiston Gait retail park to try to stop Krispy Kreme customers causing gridlock when a mile-long tailback began backing on to the M8.

Edinburgh Evening News reported that pedestrians were queuing in wintry conditions for up to an hour, but the delays caused by banked-up cars had been worse, with motorists waiting in line for the drive-through service for up to two hours.

Napier University students Melinda Garrott and Elise Setter told the paper they took public transport to reach the store after getting free samples in the city centre.

Garrott said: "We got the bus. It's about 25 to 30 minutes, but we had no idea where the store was so we got lost. It was raining – we had to get a taxi. We then waited about 40 minutes in the queue, but they gave us free doughnuts so it was OK."

Health campaigners said they were appalled at the number of people prepared to wait in their cars to buy the cholesterol-packed snacks.

Tam Fry, for the National Obesity Forum, said: "If Edinburgh is overweight today then it will certainly be obese by tomorrow."