The postings of a specific individual are not important for great companies. Its the mass. They search for patterns and want to use this patterns for advertisment or to lead your use of the internet. The postings or information of one single individuum may be not even necessary after the analyis. And even if they could use them for some purpose, after 5 years or so, they arn’t current anymore. In this time, there will be 1000s of users who spend their data.