That said, their constant "...at the cost of a raid tier..." excuse is getting old. We should just call their bluff and say sacrifice the raid tier and give us race-specific buildings for our garrisons.
It's just a handy reference to explain the level of resources required to do some of the things that might be requested. As has been evidenced by this thread, it seems that when we say that, it can (amazingly) be misconstrued.
I know it's easy to envision Blizzard as a mysterious Willy Wonka-esque magic factory where unfathomable entities craft limitless wonders. As cool (disturbing?) as it would be if we had a bunch of orange-skinned green haired gnomes running around to do our bidding, we don't (but we're working on it). In the meantime, there are real people working long hours with mouse, keyboard, and tablet to bring those wonders to life. It's hard work, and it's held up to an exacting standard.
The long and the short of it is that when we say that, we're not necessarily literally saying that "It's this or a raid tier". It's just shorthand for the amount of resources it might require to accomplish something. It's more like: 'this' or 'more content elsewhere in the game'. Some of you mentioned that you want 5-mans. Well, then the question becomes: Do you want a set of Garrison buildings for one new race or a 5-man? Or a new questing zone? Or new creatures, items, and gear? Or, indeed, a raid tier? So on and so forth.
It's merely an expression of equivalent effort to get across a point that no matter how many creative people we have working, we are always only be able to accomplish so much with those specific resources in a specific amount of time. And that means we have to prioritize what we do. We have to know when to call a project done, and move on to something else, and when to delay an 'Oh, that would be cool if' for later. Feature creep is a real thing, and it can cause an entire project to end up on the cutting room floor.