source: "Apple doesn't retain any transaction information that can be tied back to you—your transactions stay between you, the merchant or developer, and your bank or card issuer."[0]
Note how that statement is worded. "Apple doesn't retain" means they very well have access to the transaction info, they're just not storing it. I wouldn't call that designed in such a way that they can't read your transactions. It's more of a promise, similar to how google analytics promises to remove the last octet from IPs if you enable a flag.
It's worth noting that the merchant, bank, and credit card issuer can and do regularly sell that information off in de-identified form. Card networks especially like monetizing the data since it's very powerful.
I can't find the page describing the program on Visa's website, but their privacy opt-out describes it pretty well [1].
Yes but they'd do it every time you use your card anyways. So back to cash only? In the US you're screwed without using credit cards and in Europe I would not want to go back out of convenience.
Carrying 800 grams of coins around me all the time sucks.
You are thinking Apple Card, the Apple credit card, which is different from Apple Pay, the payment platform. That said, I don't disagree that GS almost certainly collects every bit of data they can.
source on this? AFAIK apple doesn't share it, but they definitely have access to the data.