Doctor friends say they often get a ''so, I've got this weird pain in my ...'' response when they reveal what they do.
Working at a recycling centre is a springboard for the ''remember when you used to get 4 cents back for an empty soft drink bottle?'' conversation.
There's a lot of nostalgia for the bottle refund system for any of us who were children in the 1970s or earlier.
It's not surprising, when you think you could trade in a couple and get enough cash back for a cream doughnut.
I remember the thrill of collecting soft drink bottles and taking them down to the corner dairy; the glass was thick and scratched from being refilled many times.
I'm always asked, ''why don't we still have that system?'', and I have to confess that I don't really know.
It was phased out as companies stopped refilling bottles and switched to disposable ones. Single-use bottles have no value to the parent company, so there was no longer any reason to pay for their return. Drink containers had joined the ''waste stream''.
But some places stood against the tide. South Australia is the closest example to us.
In 1975 it introduced a container refund system that required drink companies to give a refund for empty bottles.
The system is still in place today, and is loved by the locals.
My boss Sue Coutts, who is the general manager of Wanaka Wastebusters, visited Adelaide last month to speak at the Community Recycling Network of Australia conference.
She was amazed at the lack of litter in the city.
In fact, when she wanted to find an abandoned bottle to take to the refund depot, it was almost impossible.
''I searched for two days before I finally found one tucked into a hole in a fence on a building site. Empty bottles are like cash. People pick them up as soon as they find them,'' she told me when she got back.
Everyone she spoke to, from taxi-drivers to shop-owners, was proud of how clean their town was and loved the container refund system.
The comment they all made was ''I just don't understand why everyone doesn't do it''.
So why aren't container refund schemes popping up like mushrooms? Well, they're not easy to introduce.
As in most industries, there are vested interests that prefer the status quo.
Container refund systems have generally been resisted by beverage companies.
The price for their product goes up by the amount of the deposit.
Compared with the current situation, where councils pick up the tab for recycling drink containers as part of kerbside recycling and beverage companies voluntarily contribute relatively small amounts of money towards clean-up campaigns and public place recycling, you can understand why it is not appealing.
In 2011, the Northern Territory in Australia decided to introduce a container refund scheme similar to the one in South Australia.
When a public relations and lobbying campaign didn't stop the state government bringing in a cash-for-containers scheme, Coca-Cola led a successful court challenge.
The federal court found in May 2013 that ''cash for containers'' breached the Commonwealth Mutual Recognition Act 1992, which ensures goods and services are provided in all state and territory jurisdictions under the same conditions.
But it wasn't the end of cash for containers in the Northern Territory, which was already popular and had doubled recycling rates for containers in a year.
The territory government covered the costs of the scheme ($1 million a month) until an exemption from the 1992 Act was granted in August 2013.
The cash for containers scheme now seems to be well-established in the Northern Territory.
Other Australian states, and even the Australian Federal Government, are now looking at whether they should introduce container refund schemes, so the battle is being waged all over again.
On one side is the Boomerang Alliance, an alliance of 30 community and environmental groups that wants more container refund schemes adopted.
It says cash for container schemes have a proven track record of reducing land and marine litter.
On the other side are beverage companies, and environmental group Keep Australia Beautiful, who advocate for more of the status quo - that is, kerbside recycling and public recycling bins.
Keep Australia Beautiful admits it receives about a third of its income from Coca-Cola.
What is clear is container deposit schemes are effective in reducing litter and maximising recycling of drink containers.
How much of a problem are beverage containers?
In 2009, Wanaka Wastebusters did a survey of all the litter we picked up in Wanaka during the Keep NZ Beautiful clean-up.
The top three brands we found were all beverage companies: Speight's, Coca-Cola and Frucor.
Litter, particularly when it is made of plastic, has a significant cost to our eco-systems, especially to the marine environment.
Sustainable Coastlines has picked up more than a million pieces of rubbish along our coastlines.
It says the worst offenders in the marine environment are single-use plastic items.
Every year, 100,000 marine mammals and one million seabirds are killed by rubbish at sea.
Plastic fragments and containers travel on the surface of the sea to end up in massive gyres of microscopic plastic soup, or mixed in with sand on beaches.
It is time we had a serious conversation in New Zealand about whether we should follow the lead of South Australia and Northern Territory, and introduce a container refund system here.
Gina Dempster works for Wanaka Wastebusters.
