I know that there are several defendants [drugs etc] even in my small area who have had deleted snapchat posts, deleted texts, deleted emails, "anonymous" forum posts etc etc etc show up as evidence in court. Now I'm obviously unfamiliar with the legal and technical means by which police investigators made things like that happen, but the fact that they happen means that we can assume that at LEAST the government has access to a record of most everything we do online. Free or otherwise.
Even ignoring the question of the government surveillance net, once your data is on that company's server, how would you even be able to reliably validate what's being done with it? By which I mean, they say they don't share it, but how do you KNOW?
So maybe we would get some pretty compelling new features in a lot of our services if we were to pay for them, but I'm not at all certain that ironclad privacy would be one of them.
In fact, I'm fair certain that it wouldn't be.