Comment by eru

I'm inclined to agree with your distinction in general. But not in this particular case:

Everybody knows, even without actually bothering to read the terms-and-conditions, that they will say that the company owns all the data. Letter and spirit agree.

In some sense reading the the T&Cs might actually be detrimental to your understanding: you might misinterpret the carefully lawyered language to conclude that there are certain limits to what the company can do with your data. But they are probably way better than you at interpreting legal terms they crafted themselves.