Googler, opinions are my own. I will say, I'm super frustrated by the Domains sale as well. I also work on Payments, and can at least give some insight here.

Googler, opinions are my own. I will say, I'm super frustrated by the Domains sale as well. I also work on Payments, and can at least give some insight here. The amount of data given to a payment processor definitely differs by country and form-of-payment. But one big difference is that a full billing profile tends to have lots more data than just what is required to process a payment. Many payments (like credit cards), just need a payment description, name, address, and the card details. But this doesn't always include stuff like email address, IP address, phone #, etc. So the card processor will get the minimum info required to process the payment. There are also agreements in place with what these processors can do with this PII data. I'll definitely be interested to see what Google does regarding data transferred to SquareSpace. It's unclear right now what kind of restrictions will be placed on any data (if any) that is shared with SquareSpace.