I think part of the issue - is there have been players that the Canucks want in the 1st, 2nd and 3rd that fall to them (Schroeder, Gaunce, Rodin, Jensen and Mallet) --- so they haven't been able to take WHL players then.
Then with the later picks - the Canucks have followed three mentalities -
Draft older: Grenier, Hutton, Myron
Draft Euro: Tommernes, Blomstrand, Westerholm
Draft NCAA: Connauton, Lebate, Mcnally, Cannata.
Then there is the usual - taking a flyer on players that may have 'slipped' in development-- Anthony, Friesen and Polasek
This is done for multiple reasons - Older is because, you are closer to knowing what you are getting. Euro allows them to play against men, and can get a read; and finally NCAA, is due to allowing 4 years to sign the player, rather then 2.
(please note - I have excluded Corrado.... because IMO... this is one of the best picks in years)