E tū union's Michael Wood says New Zealand's 2024 rich list, released by the National Business Review (NBR) on Monday, shows Aotearoa is "a little out of balance as a community".
The former Labour MP told AM that at a time when Kiwis were doing it tough in a recession, it seems the wealthy are doing "very, very well".
For the first time in over 20 years, property and investment magnate Graeme Hart was knocked off the top spot as richest New Zealander.
The title has been passed to the Mowbray family - the owners of toy company Zuru.
Zuru is owned by brothers Mat and Nick Mowbray, who NBR estimates are worth $20 billion. Meanwhile, Hart is valued at an estimated $12.1b.
"I thought the rich list was really interesting, the thing that stood out for me is that over the last year the increase in wealth of that very small number of people at the top has increased by $23 billion," Wood said.
"That would be the equivalent of $10,000 for every single wage and salary earner in New Zealand, and that's been at the time of a recession.
"So, at a time when a lot of people have been doing it really tough, those with the very most have actually been doing very, very well and that says to me that we're a little bit out of balance as a community."
Wood said it was worth celebrating the listed Kiwis who've worked hard to make it to the top, but he also wanted to see a similar report done to show the worth of New Zealanders in more common jobs, naming early childhood teachers and cleaners as examples.
"I know people who belong to our unions who are cleaners and they have to balance two or three shifts a day just to try and pay the rent and put food on the table," he said.
"Those people work incredibly hard and their work is important as well, our society can't function without their work, so it's kind of about recognising that everyone contributes - yes these people on the rich list, but a lot of other New Zealanders as well, and a lot of people have been doing it tough recently."
Wood also raised Aotearoa's hotly debated topic of tax.
"Yes, some of those people do contribute back a lot but for people who are actually very wealthy in New Zealand, they actually pay less in a percentage of their income in tax than the person who is serving you at the petrol station or the supermarket or you and I," he said.
"For the income that they earn, which is vast - in this case their wealth increased by $23 billion over the last year, they're paying a lower percentage rate generally than the average working person in New Zealand.
"So that's when I said 'yep, it's okay for people to do well, but I think there are some signs here that some things have got a bit out of balance in our society as well'."
Government research last year found the effective tax rate paid by New Zealand's wealthiest families was less than half of that of middle-income Kiwis.
That's because capital gains are mostly not taxed, bringing down the effective tax rate paid by the families.
The report was criticised by the Taxpayers' Union for including unrealised capital gains.
"No one in the world taxes that, and it is disinformation to encourage comparisons to those primarily earning PAYE income," spokesperson Jordan Williams said at the time.
Debate around introducing a capital gains tax was one of the biggest election topics last year, with leaders of both National and Labour ruling it out.
However, now in opposition, Labour leader Chris Hipkins has since made a U-turn, saying tax reform is back on the table for his party.
It's something the Greens have been pushing for too, but National instead prioritised tax cuts in its first Budget on May 30.
"We are welcoming in a new era of careful government spending, lower taxes for hardworking New Zealanders and a strong focus on rebuilding the economy," Finance Minister Nicola Willis said at the time.
