Fizzy drinks, chocolate, chips and other fried foods were the most common foods sold.
Professor of Public Health, Louise Signal, says something has to change.
"We see lollies and fizzy and we should be replacing them with oranges and water."
Signal is calling on the Ministers for Sport and Health to help sports clubs implement healthy nutrition policies.
"We have to make a change because our obesity epidemic amongst our children is very severe," she says.
"We've got a third of our kids overweight and obese. They're going to go on to struggle with their weight throughout their lives."
Signal says while New Zealand has a high level of participation in sporting activities, which is really good for our health and wellbeing, "we don't want it to be undone by a diet of junk food."
However Casey disagrees and says that while school tuck shops changing to provide more healthy options is a good thing, sports stadiums and sporting clubs should be left alone.
"Kids aren't fat because they have a pie or fizzy after weekend sport or as a treat at the rugby, kids are fat because of their eating habits period. So stop blaming the sports clubs and stadiums who are just trying to make it easy and make a buck."
Sam Casey is on The Country with Jamie Mackay and Rowena Duncum, weekdays 12-1pm on Radio Sport, Hokonui and Newstalk ZB