The structure of his Private Equity company, Rank Group, lets people who write rich lists attribute it back to him.
His pay-off comes when he sells the businesses for a profit, pays back the bank and pockets the difference. Based on his track record over the past 30 years he typically re-invests in another business.
Hart has almost all his fortune tied up in a multinational packaging business called Reynolds Group, based across Europe, the US and Australasia.
I imagine the workers and their families at factories in places like Richmond, Virginia, will be pleased things are improving.
They have been through tough times. Hart is an investor who specialises in buying businesses when they are in bad shape and getting them back in the black before selling them for a profit.
That means his managers make tough calls, including cutting jobs and closing offices. Ensuring the long-term sustainability and getting a business growing will eventually deliver more employment and opportunity for communities.
But: "How does one individual possibly gain any real, meaningful pleasure from such extreme wealth?" our angry correspondent wrote.
Well, the superyachts look like a lot of fun. Apart from a few very nice houses (in Auckland and Aspen Colorado) and a private jet, Hart tends to sink any money not tied up in his business empire into giant superyachts.
That's a hobby - building and mucking about on boats. He just happens to be able to afford some very big ones these days.
But, seriously, the answer to that question about "meaning" is to look at what Hart does with his life.
He hasn't spent it counting dollars. He has spent it building a business empire. That's his buzz. He told me more than a decade ago - when he became New Zealand's first billionaire - that the dollars were a "byproduct" of what he does.
"Business is what gets me out of bed in the morning," he said in 2003. "That's my hobby.
If I was a mountaineer or an athlete, or had an interest in politics or teaching, then I'd spend my day trying to do that to the best of my ability."
That in itself is hard for some to understand. Particularly in New Zealand we have never celebrated our business leaders at mainstream cultural level.
Peter Jackson has become very wealthy making movies. Lorde and Lydia Ko should also both end up very wealthy if they stay at the top of their respective fields.
In those examples we can easily see how the money came second to realising their dreams.
From time to time we talk about how much money these star Kiwis make, but mostly we take pride in their success on the global stage.
Launching a new superyacht is pretty glamorous but negotiating a fresh credit line with a European bank or analysing the supply chain problems at an aluminium foil factory isn't.
In reality, most people find the nitty-gritty of business and finance boring.
As another example, we talk about a lot about Owen Glenn's luxury Monaco lifestyle and philanthropy, but not much about the freight and logistics business he built to afford that.
It takes a very special kind of personality to create a business empire.
There is plenty of political debate about why some people are poor. But why some people get very rich is also an interesting question.
Some people are born into wealth. But many are born to privilege and comfort - and most don't go on to become rich.
You have to really want to make it. Not a dreamy, Lotto fantasy kind of desire but an actual passion that drives you to build a business.
It isn't that the rest of us lack drive or ambition. It's that we use that drive to get up and go fishing on the weekend, renovate the house or run a half marathon.
The mental energy we put into pastimes like following sport or music or playing video games is not necessarily any less intensive than following the share market.
If we focused passionately on optimising the financial return of every dollar we made - trading shares or property, doing business deals - there's a good chance we'd all be richer.
But most of us don't do that. We prioritise other things. Which is fair enough, life is short. We should try and spend our time doing what we love.
That's what Graeme Hart has done.
