Eh, you aren't sending reviewers copies so they can like the game. You're sending them copies so they can review the game, as is the purpose of sending copies to reviewers.
But on this subject, I think the ad system is completely broken. It's why clickbait articles work: the writer of the article doesn't get paid because he/she is a good writer, but because the article is popular. Technically, the writer is being paid to advertise a product. I guess you could counter this argument with the fact that the whole creative industry is broken (as 50 Shades of Grey is grossing millions, while the writer for Moby Dick died penniless), but there's got to be a way to deal with it.

Because that way reviewers are ''forced'' to write positive articles, otherwise they'll get axed by the ones they criticize.