Albeit this is a survey from an online dating site - so there is nothing scientific about it.
"80 percent reporting nothing but fun, with everyone's rights being respected." which of course you couldn't know unless all those involved were surveyed.
Though RedHotPie.com.au (!) "relationship expert" Geoff Barker says "This kind of thing has been going on since Adam and Eve," which of course begs the question. How?? Adam and Eve does not a group make - and the next people were their offspring, which takes it down a whole different path.
Funnily enough, I don't believe any of this has ever been illegal in NZ - it isn't illegal to portray it at all, despite it shocking and upsetting people. Although I don't think NZ has gone down the British path, as I think many Kiwis wouldn't know what dogging is (or they'd think it has something to do with dogs). It seems like a peculiarly British pastime for strangers to go to car parks or parks and have anonymous sex with each other, in groups sometimes. Although I understand the Germans are rather keen too.