The service they provide is to decide that it's useless on your behalf, to save you wading through useless shit.

If I pay an offshore content farm to do content stuffing, do you want my gibberish in your results?

Then it becomes a question of which algorithm you want. Filtering out daily mail bollocks is the kind of thing that keeps me coming back to google. Am I concerned about the implications? sure; but here and now, it's doing exactly what I want.