Final paragraphs from a Mark Zuckerberg op-ed (summarized: "We need your information for operation and security, but you control whether we use it for advertising.")
"Ultimately, I believe the most important principles around data are transparency, choice and control. We need to be clear about the ways we’re using information, and people need to have clear choices about how their information is used. We believe regulation that codifies these principles across the internet would be good for everyone.The Facts About Facebook | WSJ
It’s important to get this right, because there are clear benefits to this business model. Billions of people get a free service to stay connected to those they care about and to express themselves. And small businesses—which create most of the jobs and economic growth around the world—get access to tools that help them thrive. There are more than 90 million small businesses on Facebook, and they make up a large part of our business. Most couldn’t afford to buy TV ads or billboards, but now they have access to tools that only big companies could use before. In a global survey, half the businesses on Facebook say they’ve hired more people since they joined. They’re using our services to create millions of jobs.
For us, technology has always been about putting power in the hands of as many people as possible. If you believe in a world where everyone gets an opportunity to use their voice and an equal chance to be heard, where anyone can start a business from scratch, then it’s important to build technology that serves everyone. That’s the world we’re building for every day, and our business model makes it possible."