In general, I think there is a middle ground between being so paranoid as to go totally off the grid vs. submitting quietly to every intrusion just because some intrusiveness can't be avoided.
First, I think it is important for us to be educated in what exactly we are giving out, so we can make intelligent, informed decisions after we've weighed the risks vs benefits.
Second, I don't mind things like the records my bank, cc, or phone company keep, because they are necessary.
But other things are not so necessary. Those, I avoid.
For example, I don't put anything other than the bare basics on Facebook, nor use insecure email for sensitive communications. Like many others, I use passwords on my wireless and employ commonly available and used methods to prevent cookie tracking by places I don't want tracking me. I block ad sites and others with the Microsoft MVP hosts file.
I know it's fun to laugh at tinfoilers - they
are over the top.
But people taking an interest in and seeking to be in control of just what personal information they are leaking to whom and for what purposes shouldn't be scoffed at as if they were also tinfoilers, IMO.
It's much healthier for everyone for the public to keep an eye on these things. And it's often effective; public pressure has caused various sites and companies to change their invasive policies as a result.