> I find the Dutch way (slightly) crazy, as someone from NZ for the most part, you just don't file taxes and it works out.
This is generally the case as long as you do not deviate. In the past I requested to delay having to file taxes and they rejected my request because I did not have to. The 'but' is that as soon as you screw up, or one of your bosses screws up, or you forgot to file something, you have to file from that point onward.
It is always a good thing to do anyways as you might get money back.