He unloaded the treats from the back of the lorry and shared them out with motorists who had been parked up for hours at Lindisfarne, Northumberland.
Mechanical engineer Les Goff from Leeds was also stuck and helped the driver Jon Gowing to share them out.
Mr Goff, who is also guitar tech with the band the Pigeon Detectives, was travelling home to Leeds from Edinburgh when he got stuck.
Speaking from the Lindisfarne Inn on the A1 after being trapped by the weather all day, he said: "The traffic had been stopped for a couple of hours so I went for a walk for a couple of miles to see if I could help, but I still couldn't see the start of the queue.
"I was walking back down the hill when I saw the Greggs guy at the back with the tail-lift and he just said 'Do you want some cakes'?
"He asked me to take some to the other drivers and he walked up the traffic and I walked down the traffic withdoughnuts, vanilla slices and cakes, handing them out.
"He was a top guy. He said if he hadn't delivered them by a certain time, they would go to waste.
"Obviously it was freezing, I couldn't feel my fingers and toes as I was walking along with this tray of cakes."
Roisin Currie, people and retail director at Greggs said: "We are incredibly proud of Jon and his act of kindness in what must have been a very tough situation for him and all the other poor people stuck on the A1 in this cold weather.
"We hope that his kind gesture was able to help make everyone's day a little bit better.
"Well done again Jon, a shining example of how we do things at Greggs."