It looks like it has something to do with being a _seller_ on Amazon. Had the email been sent by someone with a clue, it would have been explicit. Instead everyone is just speculating (including me).

I didn't get that from the thread title ("user's e-mails") or the Register article [0] which says:

> Amazon's UK press office acknowledged that the email was genuine, saying only: "We have fixed the issue and informed customers who may have been impacted."

and

> [...] this is not a breach in the sense of a hack while maintaining that the snafu is an inadvertent technical error and that they emailed customers from an abundance of caution.

Looks like they've ballsed up the incidence response quite badly, and seems to be Amazon's fault.

[0] https://www.theregister.co.uk/2018/11/21/amazon_data_breach/