Guess I should've made my post clearer. I know it is possible to have cross-platform MP. FFXIV has done it between PC and PS3.
Even just merging PS3 and PS4 together (and maybe XB360 + XBone) may help. We know it's possible because tiny studios like Arrowhead Game Studios managed to make Helldivers PS4 + PS3 + Vita cross-play.
I'm from New Zealand too and to add insult to injury, we have to play with Australians 
But there is more than one reason why we have empty games and it is partly due to play numbers but mostly due to the strict ping/region locking they have in place.
I believe people in UK are having the same problem, being an Island Nation away from the main land mass..
Nope. If you have a good internet connection in the UK you get matched all over the place. I get matched with Americans (both northern sorts: proper and Canadians) and all of western Europe regularly.
While it may be latency-matching, there doesn't seem to be region-locking as per the old days of NTSC / PAL / far east.
I sympathise kiwis being forced to play with ozzies, especially since most of them just seem to moan about their poor connections 