Yea. Every large company deals with “big data” as a pool of information. But WalMart doesn’t sell off your personal history to third parties, as far as we know. (But, that’s why Amazon’s not a monopoly — anything Amazon has you can get on walmart.com.)
The government is going to have to deal with those monopolies in the context of existing law. Facebook at this point is clearly a monopoly, but the difference is that they don’t pose a risk because they’ve gained pricing power, but because they pose a risk to personal privacy. Google is a bit of a different cat — it acts more like a a public utility at this point.
Bottom line is that it needs to be illegal to sell our buying and clickstream histories, regardless of if that information is tied to our name, physical address, or IP address.