Really? I watched the talk, I didn't see any evidence or concrete claim that it was actually implemented. I'm 100% against surveillance, BTW.
I don't think what Snowden and the PM were saying were so incompatible - it's a word game. Sir Bruce Ferguson (ex head of the GCSB) said on RNZ that surveillance is an agent actively looking at data, so "mass surveillance" would be agents actively looking at 4.4M peoples' data. Clearly that's not happening, so John Key can claim that there's no mass surveillance here with no conflict. Snowden said he routinely saw New Zealanders' data, but the Americans can collect all that data with impunity since we're all filthy foreigners to them - there was no evidence presented that it's the GCSB actually collecting it.
This is why surveillance, like tax, needs international laws these days - domestic law is mostly irrelevant unless you're the US. In our case the US can collect our data with no issues since basically all our internet goes through there, and we can just ask them for it if we want it. Everyone can say they're not doing any wrong with no fear of contradiction, and everyone is happy.
Except us, of course, because, you know, we're being constantly monitored.