There's a key point here: > Facebook provides detailed demographic information to site owners, using the profile details of people who didn’t log out of their

There's a key point here: > Facebook provides detailed demographic information to site owners, using the profile details of people who didn’t log out of their site and happen to stop by our site. What about those who have logged out of FB, or don't have a FB account. They don't get counted (EDIT: along with the "tech savvy" who block such things, as kuratkull pointed out). What percentage of site viewers is that? How do we tell? Secondly, if one puts up a site to serve a particular group, and others end up viewing the site, does that give one an obligation to serve these others? Is it necessarily even a good idea to do so?