You have to keep in mind that there are different gaming cultures clashing at such events. The pace of the game is decidedly slower than in the US, which results in lower point limits due to the time. It is possible to play faster, sure, but not common at European tournaments, so why change it with a majority of teams attending being European?
Just as with national competitions in other sports, not always the 'best' players are called upon. It's also about team play and those kind of things, in 40k and whfb as a teamsport just as well as in soccer or basketball. I mean, most important is that most people attending there have fun. The US team announced that it will open up spots on the team significantly for next year, btw (giving it to certain tournament winners and the likes).
Now you can of course argue that without SCs and with the team dynamics this is quite removed from 'standard' 40k tournament play, and that is fair enough. A fact is nevertheless that, as far as it goes for Europe, the best players attend, and last time I checked the Americans did not send nobodies over neither, be they the very best in the US or not. It doesn't call itself the Warhammer World Championship, or European Championship, but a team championship, suggesting it is different from standard tournament play to begin with.
