Normal people are used to having the luxury of being very open about almost every facet of their lives and not having to worry about it biting them. The privacy paranoids have largely been, well, paranoid. This has been changing over the past decade or so, but most people still don't believe it. Not really. Apps like this will change public perception, and have a backlash against permissive default privacy policies. At least I hope so.
Big data and user profiling is a somewhat recent trend, if you consider the age of the internet. It used to be that free web services merely showed you ads, and people got used to that. I don't think most of them have realized just by what order of magnitude things have escalated, how much information they are making public outside the immediate app and connected friends and how they have become a product for these enterprises to sell.
