Thats is very easily noticed if you go to Weeze. I was there this week and from many (majority) passengers to airport staff to 2 of the Ryanair stewardesses of my flight, they all were dutch! I then checked it out at Google Earth and really it is SO close to the Netherlands and a bit in the middle of nothing of Germany that is immediatly clear that at least half of the people that use the airport are Dutch.