It's all well and good if you can find good candidates who already live where you are located, but the article that Garann is responding to here is about how there are no such candidates in Austin without a job. The only choices left to companies there are now (1) relocate candidates who most likely don't want to live in Austin, or (2) relocate the entire company, likely losing the employees that you already have because they are the ones who do want to live in Austin.
It seems to me that, unless you're a two-man startup, relocating the entire company is clearly going to be more expensive.