This is great, and now let's say I want to productize this "sponsored by X" feature so other sites can use it. I can't assume every site owner wants to deal with figuring out who's the sponsor each week, so we'll automate that with some backend that serves the correct sponsor. We'll want to know how many people see the link and how many click on it, because we (and our sponsors) want to know how well these links work…
For example, I'm uncomfortable serving ads from large networks because I don't know what the end-user will see and because it's nearly impossible for me to know how my users are being tracked. If your proposed solution was open-sourced and gave me full control of user data, I think that would make all the difference. With existing solutions, company A tracks users and iframes company B in so they can get in on the action. And maybe company B wants to loop company C in, too?
Many advertisers deliberately obscure these things because they're either unethical or part of their "secret sauce" -- it's less users having an issue with their view & click being recorded.