Junk mail is in the spotlight after a religious propaganda booklet was sent to households across the country, many of which were dumped in bins - and some environmental groups are saying it's time for a ban.
One of the groups calling for tighter regulation is The Rubbish Trip. It believes banning junk mail is an opportunity for New Zealand to minimise the waste it produces,
The Rubbish Trip anti-plastic campaigner Hannah Blumhardt says she'd like to see junk mail phased out.
"Producing more paper or cardboard than we can recycle onshore means having to export paper and cardboard recyclate overseas for processing, often to Asia, which has a carbon footprint."
Earlier this month, Newshub reported that a 94-page religious propaganda book called National Sunday Law, which warns of "a stupendous crisis" awaiting mankind, had been delivered to 1.1 million households throughout New Zealand - something that shocked another waste minimisation advocate.
"It's not just the huge waste of trees and resources needed to produce it, it's the cost to councils and households that are left with the responsibility of disposing of the material," Ecomailbox waste minimisation advocate Charlene Fitisemanu said.
"Unwanted mailbox marketing material is a huge problem for NZ household bins."
But the Labour Government has no plans to ban or limit junk mail as part of its work to reduce waste, a spokesperson for Environment Minister David Parker told Newshub.
While the central Government doesn't have plans to limit junk mail, the Wellington City Council last year voted in favour of the Solid Waste Minimisation Bylaw - which included the restriction of unaddressed and advertising mail.
"Looking at the bigger picture, most junk mail tends to be advertising ... getting people to buy stuff that will ultimately end up in landfill," Blumhardt said. "So both the junk mail and the purpose of the junk mail are fuelling a level of wastefulness that does not align with the need to reduce emissions and waste."
How have other parts of the world regulated unsolicited mail?
Many countries around the world, including New Zealand, have an "opt-out" system - a simple 'no junk mail' sign on the letterbox.
But many of these systems aren't enforced by law. In the Australian state of New South Wales, for example, putting unsolicited mail in 'no junk mail' labelled letterboxes is against the distribution industry's Code of Practice, but not illegal.
NSW, however, is more strict on where advertising material can be placed; it can only be deposited into letterboxes or under doors. Employers can be held responsible for depositing advertising material on vehicles with on-the-spot fines, according to NSW's Environmental Protection Agency.
In Europe, the Netherlands has gone the other way. Its capital city Amsterdam has an "opt-in" system - where people have stickers saying 'yes' to junk mail, instead of 'no'.
Those who don't want advertising simply display nothing on their letterboxes - and that is enforced by law. On January 1, 2018, Amsterdam introduced legislation where businesses can be fined up to 500 Euros ($NZ830).
Last year, several other Dutch jurisdictions introduced that same legislation, despite the country's ad industry attempting to reverse it.
According to public broadcaster NOS, the introduction of the 'opt-in' sticker saw only 80,000 homes receive junk mail in 2019 - compared with 210,000 the year before the legislation was introduced.
In the UK, there's a national data file called the Mailing Preference Service (MPS) - where consumers can indicate if they don't wish to receive unsolicited mail. Advertisers are urged to check if people want to be contacted by mail and give them the opportunity to decline.
"Use of the Mailing Preference Service is not a legal requirement but is a strong plank within the self-regulatory framework of the Direct Marketing Association," the MPS says.
"Its use is a condition of the Direct Marketing Association's Code of Practice and the British Codes of Advertising and Sales Promotion administered by the Advertising Standards Authority.
"All mailers should ensure that their noncustomer mailing lists are screened against the Mailing Preference File."
Back home, while the likes of Wellington and Auckland Councils have introduced bylaws around junk mail, Auckland has never fined or prosecuted anyone, the NZ Herald reports.
The National Party doesn't have a stance on a junk mail ban, and ACT environment spokesperson Simon Court said businesses and other groups have a right to communicate with their communities.
"They should not be subjected to Government bans on how and where they communicate, just because some people don't like the message.
"Many local councils have enacted bylaws which set out the conditions for contractors who deliver unsolicited mail.
"Residents who do not wish to receive unsolicited mail already have the option of indicating this with a sign on their letterbox."
Court said there are plenty of options for unwanted mail to be recycled.
"Most local councils already provide extensive recycling services for paper and cardboard, and these materials can be reused again and again."
The Green Party agrees a total ban on junk mail would raise freedom of expression issues.
But Greens environment spokesperson Eugenie Sage said distribution companies need to respect "no junk mail" signs.
"The volatility in international market prices for recycled paper and cards has created challenges for recycling operators here in Aotearoa/NZ.
"Mandatory product stewardship is about ensuring everyone contributes to [the] cost of dealing with products at the end of their life, manufacturers, brand owners, retailers, and consumers.
"No scheme has been proposed for junk mail. Other waste streams such as tyres and electronic waste were identified as having a higher priority because of their environmental impacts."