This is really dumb. Developers that buy fake reviews are in clear violation of the developer agreement. Apple should not be spending time & energy removing fake reviews, instead they should warn the developer once, then kick them off the App Store!
Easier said than done. How do you prove the developer was the one that did this? If your policy were enacted, what would stop competitors from purchasing fake reviews for your app until you had your app removed from Sale.
Slippery Slope.