No, not throwaway projects. Real projects. And if they are late or poorly implemented, well, they would have been that way had you hired the sap anyway. But now you can just quit paying him, and try again.
Anyway, companies that have the time and resources are turning to this more - the summer internship program at microsoft is actually a 3-month interview, where the intern works on real code and gets a real review.
Which is great for people trying to make rent who are one paycheck away from living on the streets. Dick.