The public servant who regulated and defended gambling law says SkyCity's expansion plan is the right time to ask if pokies should be used to fund charities.
Former Gambling Commissioner Peter Chin said there were "huge moral challenges" around funding community events from gambling proceeds.
"Is this the appropriate way to provide community money?"
Mr Chin, who stood down after six years as commissioner in 2010, said there were questions to be asked over the viability of a convention centre which required gambling money to be profitable.
He also said the negotiations called time on the relationship between pokie machine money funding community groups and the pubs, clubs and casinos the cash came from.