[ivankirigin]

The quoted statement is false. You could have everything public, or everything shared with friends only, and it wouldn't matter with respect to advertisers.

Yes, facebook benefits if you share more on facebook. Similarly, every other website on the planet benefits more if you use it more.

A common idea is that facebook makes decisions based upon making money from advertising. Here, the accusation is that facebook is pushing people to be more public because of advertising money. First, facebook doesn't make decisions based upon short term monetary gain. Second, this is explicitly false, as I've already outlined.