It's also a lot easier to stay objective when friends are involved, because you have a history of them and an understanding that goes beyond what you'd have with some suit offering money. People are just naturally going to show more sympathy for those who they are closer to and are going to naturally feel more inclined to believe they're doing the right thing when it comes to them.

These statements absolutely contradict each other.

An actual lawyer would also disagree on the friends statement and details why.

For established AAA devs, their games will get exposure no matter what. They wouldn't be able to pay off more than a few people at best,

Citation on this is needed. AAA studios have LARGE marketing budgets.

See this link for contracts for the XboxOne and PAX.

See the Shadow of Mordor deal for a game specific example.

Here is a specific article detailing Brand Deals which includes the following quote.

The company invites YouTube 'influencers' to create videos of its forthcoming games on a commission basis. One participant, who asked to remain anonymous, was paid £10 for every 1000 views of the video he created for EA Ronku. In his case, the agreement was brokered on the proviso that he didn't draw attention to any of the game's bugs in their commentary, ensuring the game was presented in only its best light.

EA, which declined to be interviewed for this article, is not the only company to offer advertorial deals. According to one source, who asked to remain anonymous, Ubisoft paid a prominent YouTuber (who is represented by Channel Flip) £8000 to attend Gamescom in 2012 and create a series of videos exclusively about the company's games.