The author, Will Oremus, supports the assertion you highlighted in the portion of the article that you removed from your quotation with brackets and an ellipsis. In Oremus' original, the words "only with great reluctance" link to a previous article [1] by Oremus about the genesis of Google's advertising strategy, and he goes on to quote Brin and Page's 1998 paper [2] criticizing ad-funded search engines as inherently biased. The sourcing on Oremus' anecdotal knowledge of Zuckerberg's indifference to advertising is rather thin, but it's also a typical bit of color from a tech writer who, readers can assume, knows a lot of people in the industry. In any case, it strikes me as bad faith to argue that an author doesn't provide support for his assertions when you have excised some of that very support from your quote of the article.
[1] http://www.slate.com/articles/business/when_big_businesses_w...