Four years ago, Moxie Marlinspike offered a good explanation of why this "vote with your feet" approach doesn't really work, at DEFCON 18. His talk is called "Changing Threats to Privacy" and I highly recommend watching it: https://www.youtube.com/watch?v=DoeNbZlxfUM
If you're impatient, you can skip the first 10 minutes and 40 seconds: https://www.youtube.com/watch?v=DoeNbZlxfUM#t=10m40s