I see what you are saying. In principle, I agree that laws shouldn't restrict people's freedom to choose to do such things but reality is messy, as always: This

I see what you are saying. In principle, I agree that laws shouldn't restrict people's freedom to choose to do such things but reality is messy, as always: This issue is more complex than a simple principle and there are different, equally valid ways to conceptualize it: * Most importantly, we often preserve people's fundamental freedoms by protecting them. You can't agree to be slave, for example; that is, you can say you agree and even play the role, but at any moment you can walk away and sue for unpaid wages and the employer/owner will be guilty of having violated labor laws. I think people's rights to privacy should similarly be protected. * While maybe we shouldn't outlaw people's rights to sell private data, we can outlaw others from buying them. * In some circumstances, people have literal freedom but not a realistic ability to make a choice, due to lack of expertise or exploitation: We don't let people choose to be part of dangerous medical experiments, for example; the experiments must be approved. People lack the expertise to make an informed choice (and even approved medical experiments take care with how prospective subjects are informed). We don't let vulnerable populations be used for medical experiments; For example, prisoners and children can too easily be pressured into participating, against their will. I'm honestly not sure to what degree privacy fits this category; people understand the concept, but they have no idea of how their information is used and the risks of that.