The idea that someone, somewhere is making a profit on something you provided should make you happy, not sad. To make a profit, they had to be paid, and to be paid they normally have to have provided something that someone wanted enough to part with cash. That cash changed hands is not the main point of the transaction (it's a net zero for society, someone gained cash and someone lost it), the main point is rather that something of value was created.
You threw out the example of pay journals like Elsevier. It is true that for cases like that, there may be a market inefficiency that means not much value is created. But I think those are edge cases and relatively rare. Even if our worst fears about Elsevier and other rent seeking journals are true, it would still be the case that you're helping rather than hurting by providing anonymized personal data.
This seems like a double standard. Why should I be happy when corporations will regularly go to court to make sure that nothing they create returns to the public domain within my lifetime? The norm seems to be capturing this kind value wherever (and for a long as) possible, not distributing it freely for the good of mankind.
I'm not making a normative argument that this is a healthy way to live or for society to operate. In a functional community resources, ideas, and capabilities may be shared freely for the benefit of all, but it can't always go one way. That's exploitation, not community.
I'd rather hideously expensive treatments exist, even if I can't afford them, than live in a world where they're never even an option. Price can and does change over time, and those treatments become more accessible to more people. But if the treatments are never developed in the first place, then that's an even greater tragedy because then there's literally nothing that can be done to make them accessible.
You might have sold your own data for a higher price if you had known.
Especially when that private entity gains more power through my data and tries everything from questionable business practices to lobbying to make sure they, and only they, reap the benefits.
People value chemical weapons and forced labor as well. They're willing to pay a lot for them, too.
But if releasing your data leads to research that can save lives, isn't that worth doing even if someone gets rich in the process? I'd much rather there exist a million-dollar treatment that can save my life at the cost of living in debt for the next twenty years, rather than die in six months because the research was never done.
(Yes, this is a false dichotomy - there should be a better way of administering treatments and doing medical research.)
You aren't giving up something of value to you. There's zero opportunity cost involved. The value is added after your data is collected, collated, analyzed, and used by researchers. Individually, it's meaningless. Together, it's priceless.
Will someone eventually profit? Sure, but they'll do so because society benefits from the work they've done. And eventually, the cost will decrease. Would you rather have drug treatments that exist in the first place even if someone profits from them or nothing? Those are pretty much your options. For all of its flaws, the current research model at least works. The only other option, besides doing nothing and letting people die from diseases we could eventually treat, is some sort of public financing and that comes with a host of problems. Would anyone really be so foolish as to want to subject medical research to the congressional budget process, even if there's an abstraction layer between congress and the researchers? That means tradeoffs, and lots of them: for instance, Drug option A would be pursued, and option B ignored because we're already funding A even if B might be more promising later on.
We already see it with federal applied research when critical work is jeopardized for the sake of political grandstanding. Every so often, someone will trot out a cherry-picked grant they don't like and wave it around like a red flag in front of a bull. Drug companies might be bad enough, but the politicians would be worse.
I've grown cynical. My first thought on seeing this kind of form is that a third party will be making money from the information I provide somehow - whether it's through patented drugs or treatments or through pay journals like those owned by Elsevier. Neither I, nor anyone I know, will get to benefit from from the information I provide without spending money (often exorbitant amounts of it). This is the flip side of privatizing everything. Why should I lift a finger to help for-profit entities when they will not do the same to help me?