The reason why they have not been deleted is because the mods don't have solid proof that those reviews left there are fake. But the mods knows that the culprit wrote a fake review at least once, (now deleted)so they suspect he could have done the same with some of the other reviews, that's why they put rats in all of the reviews.
BTW a rat next to a review does not mean the review is fake, it means the REVIEWER is dodgy, so take what's written there with a pinch of salt...
I know it's harsh for hard working and genuine providers to have a rat in their reviews, but mods have to discourage the writing of fake reviews somehow...
WE all have ro do our part if we want a better system and report dodgy reviews...