Are they here because of our benign political and economic environment?
Perhaps our excellent trust lawyers just offer good value for money.
But perhaps it's that we don't tax foreign investments housed in those trusts.
Perhaps, most worryingly, it is because we don't require any detailed disclosure about those trusts and don't have any capacity to share information with regulators in countries that might be seeking to chase trustees for tax.
Regardless, it is a bad look. And it is hard to see what the upside for New Zealand is - a subsidy for our legal and accounting profession? John Key says it is worth $24 million to the sector.
A really cynical view might be that if you want to be the Switzerland of the South Pacific, this kind of opaque regime isn't a bad look at all.
It might encourage capital to this otherwise isolated corner of the world.
But in the current global tax environment, with the OECD looking to crack down on corporate tax avoidance, that would be a bit silly.
It is a bad look and one that could surely be dealt with by lifting the threshold for disclosure of information.
This would weed out the most nefarious players even if we keep the tax-free status for offshore investments in foreign national trusts.
A final question (so basic it should be the first, if it wasn't for the futile nature of asking) is the moral one: why do people who are already so rich go to such lengths to avoid paying tax?