A 5-year old girl was pushed by adults attending a swap-meet for Countdown dominoes.

Dunedin mum Kim Johnston took her daughter, Sophie, to Mornington Countdown, eager to swap their 10 "double-ups" for the last two dominoes she needed to complete the 50 character set.

Instead of completing the set, her daughter was left asking "why are adults being bullies?", after she was pushed around at the Sunday morning swap-meet.

"She was standing there looking at dominoes and the adults would push her out of the way so they could get to the ones they wanted first . . . it was disgusting behaviour."

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Only a small number of people who attended the swap meet were children and several of them were also pushed out of the way.

"If it was a kid doing it to another kid you would be more understanding, but if it's an adult pushing children around to get kids' toys, well, that's a big difference."

Another woman called her daughter "rude" after she located one of the dominoes she was after.

Disgusted with her experience, Johnston wrote a Facebook post that prompted other Dunedin people to share their experiences of the national swap day.

One wrote how a woman pushed her son so hard his glasses were nearly knocked off, "couldn't believe that adults were acting like this".

Another reported pushing and swearing by adults at a central city Countdown.

Meanwhile, in Mosgiel a woman selected ten dominoes from another person and when asked which dominoes she had to swap she replied "none" and ran out of the store.

Johnston said she too was stunned to make a complaint with the store, but said the staff at the swap-meet were also poorly treated by some of the adults.

Countdown head of promotions, planning and production, Sally Copland said the company was disappointed to hear that "a few customers were't getting into the spirit of the swap-meet events".

"The swap meets are a great way for our customers and their children to positively interact with both our store team, and other customers, to swap and collect any dominoes they need to complete their sets."

Katherine Klouwens, Marketing PR Manager for Foodstuffs NZ, said New World Little Shop and Little Kitchen swap events had been "hugely popular with our customers".

"The feedback we've received is that people who attend these swap events have generally been respectful and considerate of everyone who has attended."

Meanwhile Copland confirmed Sunday's swap-meets attracted "higher than expected attendance" and so Countdown stores would be running extended times this Sunday, the last day of the promotion.

"Stores are being briefed to expect larger crowds."

But do not expect Kim Johnston to return, "we will never attend another one".

Nor will Sophie, who thanks to a person who read about her plight, now has completed the full set of dominoes.