To be clear, what I meant was that I simply thing people should think about their privacy (or their personal data) more like anything else. I feel that people take a lot of the privacy they have for granted, and that such individuals often times yield a lot of their personal data to companies because they simply don't realize what they're handing over. But people never really have this problem with actual money - nobody defaults to being carefree about how they handle money (well, ok, almost nobody), and nobody buys something without having a reasonable understanding of how much money it will cost them.
My point is less about modality and more about mentality. Paying to use a website with dollars, and paying by being presented with ads, are exchanges that rely on different currencies. But you're still 'paying' in either scenario. People just don't seem to see it that way.
People can't reasonably expect to understand how all of their personal information is used because (again reverting back to economic rationalities) there is a dynamic of asymmetric information in these sorts of transactions. Developers and companies and their lawyers have a profound understanding of what information they get, and how valuable it is, because they create the agreements that users agree to, and they only have to think about their product. But this dynamic puts a massive burden on users to investigate the agreements of all the digital goods and services they use, which is patently ridiculous.
What the industry really needs are universal standards that apps and services can be certified against, which abstract complex considerations of data disclosure into a more accessible sliding scale that represents how potentially invasive something is. Akin to movie ratings or food health & safety ratings, for example.
We'll avoid ads whenever possible, but if the day comes where our expenses necessitate ads, we will be diligent about choosing an implementation that isn't awful. There are ad networks out there that don't suck.
Contribution models are nice to think about as a matter of theory, but very few people are willing to pay for content that's expected to be free. They also don't tend to scale well - I struggle to think of a single website that operates by providing all content publicly, and then funds itself exclusively through voluntary donations.
