We've caravaned in New Zealand and the rules over there can be quite strict in some circumstances, yet at the same time somewhat relaxed.
To use some of the DOC sites (Dept of Conservation) you have to have your caravan/motorhome certified as self contained. One of the requirement is that if you have a wastemaster type container to hold the grey waste it has to be sealed, like this...
While this seems like a good idea to prevent contamination of the site, there's no way you can disconnect it without spilling some. In addition some of these sites don't have anywhere to dump the water, expecting you to take it to a local dump station. So, not suprisingly some just empty it into the bush.
One commercial site we stayed at in Golden Bay was close to the beach. Nice site in traditional carefree Kiwi style. Fresh water and grey waste disposal but nowhere to empty the toilet. For this we had to drive about 20 minutes to the nearest dump station.
Kiwi's tend to take just about everything with them that you'd find in the home. We've seen full size freezers on the back of trucks. At one site someone came around offering us a full size freezer to use. It was left on site by someone and had been doing the rounds of various campers. We had no need of it but no doubt someone took up the offer.