People should own the data about them, and should be free to rent or trade usage of it to companies in exchange for money or services. Actual ownership should continue to rest with the person, however, who can revoke access the same way that a landlord can evict tenants or a worker can quit. The biggest barrier to this has been that lots of valuable data (eg. Facebook's social graph, Android contact data) is data abo…
Having a price for something doesn't exactly help victims of human trafficking (whether the illegal organ trade, prostitution or anything else). What can help those victims is regulation and aggressive criminal prosecution of anyone who seeks to gain from the suffering of others.
Unless people actually have a realistic and practical way of "revoking access" to their data which results in serious penalties for companies which continue to use said data (including company-destroying or even criminal penalties for senior managers/benefactors) then the negative-externalities of data-collection won't ever really be curtailed.