Since this topic was revived anyway, y'all realize that:
- some games don't have to be bought, since the minimum price is zero
- some games can't be bought, because their creators can't take payments
- even if someone bought / downloaded a game, doesn't mean they've played it
- even if they did play the game, doesn't mean they're writing a review in good faith
Basically: how exactly do you propose to, what, magically make people nice?
Please remember than the occasional one-star review has no effect on your game's visibility or anything.