There is a story told, I think in Ken Auletta's book, by Eric Schmidt from the earlier days of the company where Sergey proposes starting a hedge fund because they have so much better data than anyone else. Schmidt cautions against the notion due to perhaps significant legal implications.

Something that would perhaps counter this are complaints on zerohedge and elsewhere that Goldman's privacy policy on some of its data services leave open the possibility for them to use usage data for prop trading.

There must be people within Google wondering that if others are getting away with this, why can't they? There must also be people worried about the company's dependence on a single source of revenue...