From my experience I have noticed that (quite obviously) that what people from other countries consider a normal amount of drinks for a night out and the frequency for nights out varies wildly.
In NZ we drink a bit. Pretty much any day flies. If it's sunny we will have a couple on a Tuesday or Wednesday. When the weekend hits it's standard to get fucked. Most of us can sink, say 15 - 20 drinks easy.
(I don't speak for every kiwi, however I would say this culture is pretty standard regardless)