Already in current practice you generally don't identify the source, you identify the order # or invoice # in the transfer details and ignore the payer which can be and often is different from the ordering customer (family members, companies paying some bills, etc), the payer information currently gets used only in case of mistakes and such.
My point is that I'd like all these companies to do their best to treat these purchases as if they were anonymous. But your point about VAT rules is a valid issue that might have wider implications about the general necessity to store data.
"what you'll have to tell everyone's credit card company when they start disputing charges as product-not-delivered and you have nothing to counter with." that's absolutely not an issue, that might be the case for card-not-present transactions but for as long as I can remember every single pizza courier or similar would use a wireless terminal to get a chip&pin (or now contactless) card-present authorisation which can't really be disputed in this way.
Yes, you still have VAT records to keep. You also need to prove that you provided all required information to the customer under the consumer protection rules or you can end up having to refund everything going back quite a long time. All these protection rules require accompanying record-keeping as evidence of compliance, which unfortunately is going to undermine your hope to make even simple transactions anonymous in many cases.
that's absolutely not an issue, that might be the case for card-not-present transactions but for as long as I can remember every single pizza courier or similar would use a wireless terminal to get a chip&pin (or now contactless) card-present authorisation which can't really be disputed in this way.
Do you often go into a pizza place and witness a card present transaction to pay for a delivery order? :-)
Yes, that's exactly what I'm saying, almost all the pizza/goods delivery/taxi/whatever are card-present transactions; whenever I order something like a pizza for delivery, the delivery dude arrives at my door with a wireless card terminal and I pay with my card present (chip+pin or contactless if the amount is small) upon receiving the pizza, and this has beeen this way for so many years now already that I don't remember when they switched from the earlier model, now businesses such as these usually don't have card-not-present acquiring contracts, possibly for cost or fraud reasons as both these things are worse if you have card-not-present permitted.
How are you going to identify the source of a wire transfer if you don't have a customer to match it against?
Also, if you're selling online then anything service-like is already caught by the EU VAT place-of-supply rules (which require verification of the buyer's location and keeping adequate evidence for up to 7 years) and there have been proposals to extend that to sales of physical goods for some time.
If you're delivering pizza, then you don't need to store every order's phone number and address forever; and if you don't store the delivery data beyond the delivery, then if someone requests all the data you have on them, then you can honestly say "nothing".
And that's exactly what you'll have to tell everyone's credit card company when they start disputing charges as product-not-delivered and you have nothing to counter with.
I'm afraid you're being extremely optimistic about how much personal data processing can be avoided in even these everyday situations. And this is before you do anything like marketing, customer relations, logging use of your electronic systems, having any employees, paying any suppliers, etc. I don't doubt that some cases where companies currently have your data could be avoided, but I suspect 50% is a gross exaggeration.