Famitsu rates based on advertisement and "respect" for the fanbase of any particular franchise. You can release the biggest pile of shit and get top scores as long as your game has Final Fantasy in the title. You'll never see them slam a big title. See scores like 39/40 for Resident Evil 6. What an industry paragon that game was, ey? Pretty sure they never even denied that.
They basically have to do it that way because very few actually buy the bloody mag. It's weekly and it's ridiculously expensive. People tend to just grab it from the shelves, flip through it, see the stylish advertisements, and then they put it back. Games retailers also display the review pages right next to the games they wanna sell.
Besides, the bodies of the reviews are laughably insubstantial and usually filled with with empty catch phrases, making you question whether the critic has ever touched the game in the first place.
To further illustrate my point, here's a typical Famitsu review in its entirety:
"9 - With three different character types to choose from, as well as many different Commands and Styles, there was an amazing variety with what you can do in battles. When the Commands you can use increases, you can choose your own way of fighting the battles which gives a nice feeling of freedom. The boss battles were quite lively and exciting, and you can have fun with the direction of them."
This is one of the four reviews to Kingdom Hearts: Birth By Sleep. (the other 3 aren't any better) Anyone could have made that one up without ever touching the controller.
You wouldn't have gotten away with an "essay" like that in grade school.