Figures released under the Official Information Act reveal the amount won from Instant Kiwi tickets rose from $59 million in 2007-08 to $90.7 million in 2011-12.
The number of winners has increased from 9.5 million (2007-08) to 11.7 million (2011-12), the average winning ticket increasing from $6 to $8.
While the number of games had decreased over the same period from 51 to 37, there had been a move to more expensive tickets, the first $20 Instant Kiwi being introduced in 2011-12.
Over those five years, the value of unclaimed prizes or games withdrawn from sale was $22 million.
A NZ Lotteries spokeswoman said once an Instant Kiwi was withdrawn from sale customers had to claim any prize within a year.
Unclaimed prizes entered a prize reserve fund, which was used to fund special prizes and augment prize pools for various draws and games, she said.
NZ Lotteries, which launched Instant Kiwi on September 14, 1989, had never withdrawn an Instant Kiwi game from sale with all top prizes remaining, she said.
Those customers wanting to know how many prizes remained in any game could ask at a Lotto kiosk for a printout, she said.
Problem Gambling Foundation chief executive Graeme Ramsey said Instant Kiwi was at ''the more dangerous end of the NZ Lotteries product suite'', when compared with the likes of Lotto and Keno.
Of particular concern was that the age-restricted products were displayed at eye level for a younger audience, were often bought as presents for younger people and were a ''cheap gambling product''.
''I think they are enticing for young people ... They play a key part in the normalisation of gambling.''
During the tough economic times of the past few years he had expected the sale of Instant Kiwi scratchcards to have declined, not increased.
''I am a bit surprised by that.''
