just a pilot who has never seen -curved- upward (or downward) wings. <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />
No? Well if you accept a tail as a sort of wing, have a look at the attached picture.
If you want to create lift and sideforce, canted or bended wings are a good solution. You can use two boards, one for each job. But with a single bended or canted you save a lot of wetted area, which is drag. As long as the board can carry the loads, it is a good solution.