It's all fairly gentle and yet players can get rich in the process. Tamati Ellison, a one-cap All Black when he left in 2009, is thought to have secured a contract in the region of $600,000 a season, while Kaino is reportedly going to be paid $1.3 million a season.
John Afoa, who left after the World Cup for Ulster, is thought to have picked up a deal in Ireland of similar value to Ellison's in Japan. But Afoa has had to give his pound of flesh. There are 22 games plus play-offs in the RaboDirect Pro12 (the old Celtic League) and Ulster also made it to the final of the Heineken Cup - playing nine games.
The differences between the two offshore markets are stark - there is the higher quality, brutal rugby of Europe that is more physically demanding and emotionally rewarding.
Or there's the pass and giggle, financially lucrative Japanese option that takes little out of the legs.
"I would say it is similar to ITM Cup," said Nonu in regard to the quality. "The good thing is they have foreign players scattered round the teams."
Japan is increasingly winning out as the preferred option for New Zealand players. Part of that is down to their more aggressive recruitment. The 2019 World Cup will be in Japan and there is a desire to build the profile of the sport ahead of the tournament.
Attracting foreign players is a means of boosting interest in the domestic league and to do that, the Japanese realise they have to outbid the European market, particularly the French.
The money in Japan has gone up while the relatively weak Euro has diminished the true value of deals on the other side of the world.
There's also the growing belief that Japan can be a career-extender - a means of boosting the bank balance without it being terminal to future test aspirations.
Since Luke McAlister left for Manchester in 2007 when he was just 24, more players believe they can go overseas midway through their career and then come home to try to recapture their test jersey.
McAlister never quite pulled it off. His English sojourn robbed him of his step and acceleration. Aaron Mauger, who also left New Zealand young to play at Leicester, was keen to come home in 2010 for a crack at the World Cup only to be forced to retire due to a chronic back injury.
The attrition of Europe takes its toll and, to date, no one has really managed to prove that it's possible to rebuild a prolonged test career. Japan is different.
Leon MacDonald and Troy Flavell both managed to win back All Black places after playing in Japan (although neither became a starting All Black) and now Ellison has returned to the national squad.
Kaino has convinced himself that he's heading to Japan, not forever, but on an extended sabbatical with a view to trying to regain his All Black place for the 2015 World Cup.
The mix of big pay and little play can be intoxicating, especially when there is hope, in some cases genuine, that the heights of New Zealand rugby can still be scaled. But there is a cautionary note offered by Ellison. He struggled with the lack of intensity in Japan and the knowledge that he was there for the money.
"I worked out over there that if you are really passionate about the game, you really struggle to play for those other reasons," he said from the All Blacks training camp in Auckland. "I struggled to get out of bed [to go to work] and that's the first time that's happened to me in rugby."
The Japanese predators will be circling in the immediate future. The Panasonic Wild Knights are thought to have put $1.5m on the table for Sonny Bill Williams. Hosea Gear was close to agreeing a deal with Toshiba last week, Cory Jane was set to leave after the World Cup until a tsunami struck and Isaia Toeava is believed to have signed with a Japanese club subject to him regaining his fitness.
Soon, the first question anyone will ask when a New Zealander heads offshore, is "which Japanese club?"
