It is now a crime to do a paid review for someone? If so, can you point me to the law stating this?
If not, then you are making a big assumption and could hurt someone's business by blasting all over the internet "just how morally corrupt this person is".
You're completely missing the point. There is a huge difference between illegal and dishonest. As far as I know, yes, it isn't illegal to pay for a published review but it surely is a dishonest business practice.
At the very minimum, this website is probably deceiving their readers by publishing these so-called "positive" reviews.
They are careful with words; they are only saying that they would not publish a negative review. They are not directly promising a positive review. But it would cost them $50 not to publish a positive review, so they are very likely to publish an undeserved positive.
Crime? No. But the whole point of a review site is the implicit promise to readers: "We will tell you whether this is any good or not". If what they actually do is to publish only positive reviews, for a fee, then they are deceiving their readers into thinking that advertisements are reviews.
Sure it's legal. All kinds of things are legal. Some legal things are harmful and dishonest, and should be exposed.
I never said anything about a crime. Reviews are only worthwhile if they are honest. I believe that any site caught soliciting pay to play for positive reviews should be called out. Not sued, just publicly shamed.
It goes both ways, Belkin caught tons of flack for soliciting positive reviews on Amazon Mechanical Turk.
If not, then you are making a big assumption and could hurt someone's business by blasting all over the internet "just how morally corrupt this person is".