Ms Kupa's friend, who helped her gain access to the field, was also issued with a pre-charge warning for being a party to disorderly behaviour and trespassed for two years.
Today, Lisa Lewis, who was fined $200 for her 2006 bikini-clad streak during an All Blacks vs Ireland test at Hamilton's Waikato Stadium, was disgruntled that Ms Kupa got off scot-free.
"All streakers/pitch invaders should be charged the same," she said.
Ms Kupa should also have been charged with indecent exposure given that she was naked, and assault due to the slap on Israel Dagg's behind, Ms Lewis said.
Christchurch builder Adam Holtslag, 28, was earlier this year convicted of offensive behaviour and fined $500 for his streak at Dunedin's Forsyth Barr Stadium, from which he was also banned for two years.
Today he was shocked that the same treatment wasn't given to Ms Kupa, saying it was "a bit one-sided".
"She touched a player. And she was showing a bit more than me anyway," he said.
"It should be the same rule for everyone. If anything, I thought they would've been a bit harsher on her after the one I did."
Family First said the decision not to prosecute Ms Kupa "sends a dangerous message to copycats who also want their minute of fame".
A letter would be sent to Police Minister Anne Tolley asking her to review the decision, national director Bob McCoskrie said.
This afternoon, police said they stood by their decision, but said they had learned from the incident and future streakers could be treated more harshly, taking into consideration the "possible wider implications".
"I believe that our staff made the right decision based on the information available to them at the time and given the particular circumstances of the incident," Eastern District Commander Superintendent Sandra Venables said.
"That said, with the benefit of hindsight, we are mindful of the wider implications in this case.
"In light of that, I expect that in the future, Eastern District police staff will be more aware of the possible implications around charging for this sort of offence and will respond accordingly."
Pitch-side officers would be on high alert at next weekend's Ranfurly Shield challenge match at McLean Park, she said, warning the public to expect that any future incidents may not be treated so lightly.
"Our message is that this sort of behaviour won't be tolerated and there could be serious consequences for anyone trying to invade a sports field while a game is in progress."
Earlier, police said the decision was based on the lower level of her offending, her attitude when arrested and the fact that she was sober. She was not deemed a risk for the rest of the night.
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