The kiosks have also been identified as a risk of money-laundering for organised crime groups.
Green Party co-leader Metiria Turei responded by saying the Government should can its deal with SkyCity and look at ways to stop casinos benefiting from the proceeds of crime.
"The concessions SkyCity are seeking in return for building the conference centre, like more Ticket In Ticket Out machines, are likely to lead to more money laundering at the casino,'' she said.
"Rather than change the law to allow SkyCity more opportunities to cause harm, the Government should investigate ways to ensure the casino pays back money stolen from hard working New Zealanders.''
Mrs Turei said changes to the law could include amendments to the Criminal Proceeds Act or a ban on Ticket In Ticket Out machines.
SkyCity Chief Executive Nigel Morrison said tonight that the Greens' statement had "no substance to it at all.
"Any illegal activity by customers is bad for SkyCity's business and we work closely in a collaborative relationship with the police and other authorities to ensure it is dealt with immediately and appropriately.''
He said SkyCity is proactive in its approach on illegal matters, alerting the police or other relevant body if and when they occur.