data brokers

Did you know that there exist companies that sell information about you - about how much money you make and whether you’re pregnant, divorced, or trying to lose weight? How much do data brokers know about individual people? They start with the basics, like names, addresses and contact information, and add on demographics, like age, race, occupation and "education level,", but that's just the beginning: The companies collect lists of people getting married, buying a home, sending a kid to college—or even getting divorced, expecting a new baby, hobbies, purchases, donatins to charities, etc. Why would this all be interesting for your doctor or for your hospital? See here:

http://www.bloomberg.com/news/2014-06-26/hospitals-soon-see-donuts-to-cigarette-charges-for-health.html