It's not about missing the privacy discussion it's about the public at large not giving a flying duck about it, regardless of what you think.
Pick a random person on the street and ask them, you need to understand that by enlarge simply by knowing about this site you are already part of a tiny subculture of of the general population, and most likely living in a walled garden as far as your social connections goes.
People don't opt in, but they don't care about their privacy just look at the amount of people that would sign up for a mailing list/club benefits at a store they'll only visit maybe once in their life for a 5-10$ worth of discount that they'll never lose - for that they'll be willing to give up a whole lot more of personal information that GA or NVIDIA GFE collects.
This doesn't excuses the practices, it's just the reality we live in.
