The Problem Gambling Foundation says children should never have been able to purchase gambling products ... even for their parents.
Currently Instant Kiwi tickets are the only Lotto products which are age restricted, but legislation will be introduced to Parliament this year to ban the sale of all Lotto products - in store and online - to those who are under 18.
Lotto was welcoming the change and its spokesperson Will Hine said they did not have firm data about the number of under-18s purchasing products, but it was believed the numbers were very low.
Problem Gambling Foundation advocacy and public health director Andree Froude said it was "gobsmacking" that until now children under 18 had been able to purchase Lotto tickets and many people were not aware that this was the case.
Even if a young person was buying a Lotto ticket for their parents it normalised the behaviour, she said.
"It does tend to normalise gambling and make it seem to them that there's no risk associated with it and that it's just a normal everyday thing to do, so this is really important and sends a signal that these are gambling products and that children should not be able to purchase them."
Research undertaken with New Zealand adults showed that gambling before the age of 13 was a risk factor for lifetime harmful gambling, she said.
Young people are exposed to much more gambling advertising than in the past, she said.
"It's really really important that we make young people aware that there is a risk associated with gambling, whatever that gambling is."
Gambling is continuing to evolve with the growth of online gambling and games which contain gambling elements, she said.
"We're certainly seeing more young people engaging with gambling and again being targeted by advertising ... it is certainly of concern."
The online space was driving some of the problems with gambling and young people, she said.
"They're on social media, they're very tech savvy, they're gaming and things like loot boxes that have gambling elements, they're very similar to gambling and they have to with a loot box spend real money for the chance of winning something they might want to use within the game. All of these things are exposing them to gambling."
The online environment was available 24/7 and online gambling normalised it for young people, she said.
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