Attendants stopping vehicles driving down Exchange Street have had motorists aiming directly at them - with one guard even being struck by a van.
Measures were introduced after Lucy Hall, 66, caused queues of honking cars when she blocked the passageway at the start of November.
But drivers are still refusing to comply, with the marshal on patrol on Monday, November 28, reporting he was struck by a van.
The security guard, called Daniel - who said he could not give his last name for safety reasons - said: "I had a guy drive up to me. He literally hit my legs by edging slowly towards me and hoping I'd move.
"Then he got upset and got out of the vehicle.
"He then started giving me abuse saying he couldn't get his work done, which I can understand but it's not great.
"It's only happened a few times where people have come towards us then tried to drive around us but obviously it's not very nice.
"We've got a couple of female members of staff and they get abuse all the time - people think they can get away with it."
Norfolk County Council would not confirm whether it would be taking extra measures to protect wardens and stop drivers.
A council spokesman said: "The marshals are operating from 10am in line with the loading restrictions, they are still in place."
Nearby market traders said they could understand why drivers were getting upset.
Mike Read of Mike, Debs and Sons greengrocers said he could hear horns hooting from across the market.
He said: "It's been causing people all sorts of grief.
"People have been getting really upset about it and they've been queuing all the way down from the roundabout only to have to turn around again."
Charlene Cary of Cary's Flowers described the situation as a "mess".
She said: "It's killed trade in the city.
"I want everything to be perfect but we've even had flowers damaged because people have had to walk with them.
"It all flowed so nicely before and now it's a mess."
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