I strongly agree, and can also give an example. My latest, though already quite old level, Knightmare Castle got an 8.2 by EvilMike (!!!), which I am very proud of, of course. Though, a guy called "Magic Card", who at all has 4 reviews, though it is not better than a cheap 5.2.
What the moderators should do there: of course they should not just delete such reviews, but perhaps talk to the reviewers and, if they dont respond or whatever, talk to top raters like EvilMike, Aiko, Trafton etc, if it would be justified to remove such a review.