Debt collector Colin Hardie said some debtors tried to hide but, unfortunately for them, debt rarely disappeared - and usually grew.
"Generally, with government debt, they get the money regardless. You see it on TV - if you don't pay your fines and want to go to Australia, you get to Customs and they say, 'sorry, you can't go'."
He said the threat of a suspended licence would encourage most people to pay outstanding fines, but not everyone.
"People lose their licences and drive anyway, some don't really care.
"At the end of the day, if you owe the money you should pay, regardless of who you owe it to or what the debt's for."
Nationwide, $11.6 million in fines had been paid as a direct result of the warning letters.
Justice Minister Amy Adams said the campaign had raked in $43.5 million in previously unpaid fines since February 2014.
Mrs Adams announced 30,000 warning letters had been sent in the two years to January 30. However, the documents released showed 19,567 letters had been sent since the initiative was introduced in February 2014.
The Ministry ceased actioning stop orders on July 1 last year, and was "changing procedures ... to make them more effective" - but continued to send warning letters.
Driver Licence Stop Orders since February 2014:
* Hastings District Court: 201 letters, $121,915 fine payments.
* Napier District Court: 200 letters, $134,568 fine payments.
- Source: Ministry of Justice
