Just a brief remark, Kilian wrote:

And thirdly, it can be really expensive to fly them in (ideally, the winners come from pretty much everywhere, so you have to get people from Russia and Estonia to Brussels as well as from Portugal and Norway) and it's hard to organize.

Take into account that it is possible for ppl outside of these countries to enter as well - the monuments are in these contries, but in theory a visitor from Japan or Botswana could just as easily participate and win...

BR
noorse