> It's completely useless to their organization. Junk data to be deleted later.

At least one person at Google thought it could be potentially useful:

> The report, quoting the engineer’s original proposal, gives a somewhat different impression. The data, the engineer wrote, would “be analyzed offline for use in other initiatives.” Google says this was never done.

I think Google is guilty of arrogance wrt privacy, rather than a fiendish plan to spy on people.