Whangarei gamblers spent $14.9m on pokies in the year to June. Far North punters $13.2m, and Kaipara $2.7m.
Ms Murphy said she expected the service to get busier in the lead-up to Christmas as some people realised they'd gambled away their savings.
"They still think they can play the pokies, triple their money, and buy the things they need for Christmas.
"That's what we get from nine out of 10 clients. They honestly think 'I'll put in $2, I could win $1000, or even $20 - that's more than I put in'. Then if they win, they put it all back into the machine."
She said the harm goes far beyond losing money, and often stretches relationships.
"There's always the threat of domestic violence, because it's either one partner and the other partner doesn't know, and they've spent all of their savings.
"It's a huge issue. Gambling is so huge."
The Whangarei-based Oxford Sports Trust said statistics showed between 0.3 per cent and 1.8 per cent of adult New Zealanders were deemed to be problem gamblers.
The trust is one of seven gaming machine operators in Northland and in the year to July 2016, it operated 223 electronic gaming machines in the region.
During that period, the trust's gross revenue was $11.35 million and it paid $2.27 million in government duty, GST of $1.48 million, $160,000 in problem gambling levy, and $4.63 million in community funding.
"The gambling Act is quite clear in the requirements of our venues as to their responsibilities with harm minimisation and problem gambler identification, and takes this responsibility very seriously," the trust's Don Armitage said.
"If the problem is growing there needs to be discussion between the Ministry of Health who distribute the problem gambling funding and the provider to access more resources."
The Ministry of Health spent about $18.1 million in 2015/16 on gambling harm minimisation across all areas - casinos, betting, Lotto and pokies; down from $18.5m a year earlier.
Gaming legislation required owners of class 4 machines - pokies - to distribute a minimum of 40 per cent of proceeds as grants. The Crown took 23 per cent of proceeds as a levy, and just 1.51 per cent of proceeds were distributed to the community.
Associate director of Auckland University's Centre for Addiction Studies Peter Adams said simple steps could be taken by local or central authorities to reduce gambling harm. But he said there were too many groups with a "high reliance" on the proceeds of gambling to expect any meaningful change.
"I can't see things changing in any significant way until community groups and the Government say we are not comfortable accepting money from problem gamblers.''