It's also trivially defeated by the kind of financial centralization that would necessarily follow in this kind of mass-adoption scenario: the payment processor

It's also trivially defeated by the kind of financial centralization that would necessarily follow in this kind of mass-adoption scenario: the payment processor (BitPay, Visa, MasterCard, whatever) can have a pool of Bitcoin transaction addresses that they use across all clients, and then commingle and convert client funds to USD (or whatever desired currency) before privately remitting the USD. The payment processor itself would have perfect visibility into the revenue of the merchant, but that's already true today.