[indigo945]

If you are applying to only one job, you are either in a position where you don't have to do silly homework exercises (i.e. you already have a foot in the door) or you're not doing job searches right. For most people, it is far more reasonable to assume that they might apply to 3-5 jobs at once, and going by your estimate of 10 hours of work per job prospect, they would need to take an entire week off just to get to the point where they're offered an interview.

Everything else regarding your argument has already been covered by other users.