I think if you go to multiple dealerships, you will see that some dealerships are all about selling outbacks and foresters and others like selling wrx's. Most places dont make money selling wrx's and so they don't care to work hard selling them (unless its on their used lot because used is where the real money is at). Also wrx's pretty much sell themselves. They don't have to try hard to convince someone to buy one. Generally if someone is a potential buyer of a wrx, the buyer already has the intention of leaving with one.
I'm not condoning this practice but i can see the logic behind it.
As for brz. Id need some convincing to get rid of my sti for something else. Lol