"In a place like Christchurch you'd see it with Burnham military camp, but here in Rotorua I know of half a dozen men who are a returned service personnel from Bosnia, East Timor, Bougainville who are a part of the club."
Mr Treanor said membership had been influenced by a number of factors.
"It's a changing attitude towards socialising. People go on Facebook these days, they're finding entertainment elsewhere. TV has hundreds of different channels.
"Also you have liquor outlets, you don't need to get dressed up to go down to the supermarket, you can just indulge at home. This is happening to clubs across the country, and not just RSAs but bowling clubs and citizens' clubs.
"We started talking about needing to do something five years ago but we took the initiative about 18 months ago.
"We almost missed the bus and it took a concerted effort to catch it. There were warning signs, we weren't seeing fresh faces in the place. Of course, not seeing fresh faces means a drop off in the bar takings and in the restaurant.
"With all respect, in the past the RSA operated like an old gentleman's club.
"While we're a non-profit organisation, we still have to make money to survive. When we looked at our numbers and saw where we were at, the realisation came as a shock."
In response, a management sub-committee was formed and the club began consulting their counterparts throughout the country.
"They were absolutely fantastic in their help, in particular, Napier who are very successful. We said to them: This is what we want to do, are we moving in the right direction?"
While the cheap drinks, friendly faces and rows of pool tables remain, a move has been made to encourage younger people, and in particular women to join up.
"We have an all-women team in the office who understands what the needs are of the modern woman. This has had a significant impact in the growth of our membership.
"This is a safe place to come, where no one will hassle you. We certainly have been on the fast track to modernisation, we offer Wi-Fi so you can come and work on your laptop," Mr Treanor said.
"We're also members of the chamber of commerce and go to the Business after Five events. We have representation there that talk, particularly to young businesswomen.
"Our catering team also go out to some of the businesses in the CBD and supply their morning teas and lunch, and that's had an impact, with some of the business people coming down to the RSA. For some, it's the first time many of them have been inside.
"Our long service members love it. They make up two-thirds of our membership base and, while we are widening our horizon, our principle of helping ex-service people won't change. They've been very supportive and enjoy the fact that there's new faces."
Mr Treanor said they have also revitalised their restaurant menu.
"While we still provide the meat and three vegetables for our loyal members, we also cater to the modern diner as well as children. We took it to the AGM in March and it was unanimous that we bring children into the RSA, for it to be family friendly." Nationally, the organisation has 120,000 members, 70,000 of whom do not have a service background.
The demographic change has been matched by a shift from the RSA's traditionally male-dominated membership. About a third of the members are women.
RSA national president Don McIver said their research showed many people were under the impression that they needed to have served in the military or have some service connection to join the RSA.
"I think many people have traditionally regarded the RSA as a place for old soldiers but, for RSAs around the country, that is not the case. They are community hubs where people come to enjoy each other's company, meet friends and family, and enjoy the hospitality that is on offer."