It's not "price-gouging", FFS. The price of a good or service in the market is the point at which a willing seller and a willing buyer meet. Meaning that the price of a faction change is as high as Blizzard can set it before people stop buying it. Or more specifically, until enough people stop buying it as to make it not worth the bother. Yeah, they clear a lot more of a profit for a faction change than, for instance, someone selling $25 or $30 t-shirts clears per unit sold, but that alone has nothing to do with anything. "Profit" is not a dirty word.
I wish it was cheaper. But that's true of all sorts of things I want but don't quite want to spend the money on.