It's probably something to do with having a population under 5 million - thereby giving one of the highest per-capita figures in the world!
Or maybe it's probably something to do with hard work and being willing to learn from others (fixed wing unions). Following your logic, I guess a dutch CHC captain makes the same as a KLM captain... And they both drink Heineken of course...?
Now, many of you will state the fact that airliners have larger aircraft and more passangers, therefore better pay for the pilots. Then this might come as a shock to you, but in Norway, a cab driver probably makes twice as much money as a bus driver, even though the bus is larger and can take more passengers than the taxi! How weird is that.....!?