If I can get a better fare with Canada 3000 and with more freedom, why should I bother with AC when I get only 50% of mileage which is about (50% of 920 miles per one way = 460)!? What can I do with 460 miles? It's totally economic inefficient from a frequent traveller's point of view.
Guava, are you referring to YYZ-YWG? Is it true that you can get a better fare with C3K with more freedom? $129 sounds pretty low to me. At that fare, I wouldn't even bother shopping around. As for the low mileage earnings, I thought the primary purpose was to get to your destination. Besides, what's the alternative? You mentioned C3K but they don't seem to have "real" YYZ-YWG service (I checked their schedule and they only have 1 daily flight).
For domestic North-American flights, they really should allow upgrade from L or Q fare; otherwise, there is no incentive for most frequent flyers to buy such fare for leisure purposes. They will be beaten by their competitiors in the mid-long term within North-America, and I am 100% positive of that.
I'm 100% positive you're wrong. At least for me. The incentive to buy this fare is to get to a destination at a low cost. What competitors are you referring to? I haven't been able to find any.