"A lot of kids were getting hurt ... parents were just running in and running over the kids. I was like 'oh my goodness' and my volunteers were blown away by the behaviour of the parents," he said.
After the event angry parents took to the Facebook page Egg Day Out to express their concerns. Most said they were disappointed about how other adults behaved.
They described other parents as greedy and abusive and said they were trying to get as many eggs as possible. Yvonne Pokotai-Ratana took her daughters to the event with some friends and their own kids. She said an adult set upon her younger daughter Yves to take any eggs she had collected.
"There was a point where the adults weren't allowed to access beyond, only the children. But arrogant adults ignored the commentator," she told the Herald.
"When the egg drop started the crowd of kids and adults rushed up the hill - most of whom I saw were adults being rough to others around them just to get the Easter eggs. My 7-year-old's face was scratched by an adult and she didn't even have an egg. Other children walking past were crying or even hurt."
A woman posted on the Facebook page that she ended up in the accident and emergency department with her young son after an incident at the event.
"Thanks for the A&E visit for my 3-year-old [after] getting pushed by adults and his fingers getting trampled on after egg ripped out of his hand," she wrote to organisers.
Mr Schaafhausen said a lot of planning had gone into the event and health and safety was "paramount".
Easter Monday: 5 things to do
1 The Coca-Cola Easter Show is an Auckland institution and has been running since 1911. On at the ASB Showgrounds, 10am-10pm. Free entry, rides are extra.
2 Celebrate the Croatian grape harvest Berba at Soljans Estate Winery in Kumeu. Visitors will have the chance to try some grape stomping. Free entry, $5 to join winery tours at 11am and 1.30pm (kids free).
3 National water ski championships, featuring trick, jump and slalom finals. Orakei Basin.
4 Waitakere Ranges bush walks. Good starting point is the Arataki Visitor Centre at 300 Scenic Drive.
5 The Lego Movie 3D has been getting good reviews. The Herald rated it four stars, saying "it embraces what parents and kids really love about Lego; creativity, imagination and individuality".