Lotto tickets printed on supermarket receipt paper have been found by lottery bosses to wear out faster than normal tickets.
However, a business case study found the extra wear-and-tear could be managed and was no reason not to go ahead with checkout sales, which have recently come into effect in more than 100 Countdown stores, papers released under the Official Information Act show.
Experiments by Lotteries staff pitted the standard ticket against a till-printed ticket. The standard Lotto ticket was of "very high quality" and "highly resilient to being stored in pockets and warm places" board members were told in the Lotteries Commission business plan.
"The till paper does wear more rapidly, this shows as deterioration on the edges of the paper."
But they decided the issue was "manageable", deciding to use a shorter bar code and to move critical information to the centre of the till-printed ticket.