This is the kind of stuff where the government should have a heavy hand on regulations (unfortunately the members of the government like anyone else are incentivized by money so guess who has a lot of it to "lobby" them.)
It maybe isn't an ideal solution, but it has a lot of upsides. Advertisers (and ad middlemen like Google) bet that they can sell more stuff by drilling deeper and deeper into people's lives.
But the bottom falls out of all that when people decide to opt out of large parts of the commercial ecosystem.
Track your finances instead, the same way you would with a fitness app, and get that dopamine hit from seeing your savings increase. Feel secure in the knowledge that when the next major economic slump hits -- when, not if -- you'll be able to easily ride it out, maybe even enjoy a nice vacation at discounted rates.
The massive growth of ad blockers was an immune response to the excesses of advertisers on the web. Commercial minimalism is the only way to respond to all this crap happening everywhere else.
When I'm shopping it isn't just the old ladys digging deep and long in their purse for the exact change, almost everyone pays with cash.
Maybe this exists already. The difficulty would be in offering a good usability (how do you get that Amazon product you want in your local shopping basket).
You are right about the privacy guarantee, but there is the issue of trust in any business transaction. Why am I using ProtonMail/VPN? Because they have privacy + security as their primary USP and it is reflected in their business (transparency, privacy policies, compliance, certification, etc.). They work hard to earn and keep my trust, and I pay them to do just that.
I am no expert but probably you can let your company be audited by some trusted party on adherence to privacy promises and prove that you comply.
Having that they can keep my data in storage for as long my government requires by law.
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Edit: Because this is deeply nested and tangential to the topic I created a separate Ask HN on this idea: https://news.ycombinator.com/item?id=17884474
Still a huge difference betwen that and the alternative where all three of:
- Amazon - Google - and MasterCard
knows what you've bought IMO.
This is the first Google result for “amazon.com pay with cash”.
https://www.washingtonpost.com/news/wonk/wp/2015/06/10/how-p...
It's ridiculous that credit cards, the primary mode of online purchases and strongly preferred by physical retailers, is dominated by just two/three companies... all of which freely sell your purchase histories to other companies.