Can a Shopify seller share my email and order info with other customers that I don't know?

I had a seller I attempted to buy from send me an email and copy another person from a completely separate order to an email and talk about details of both orders. This seemingly was as the result of Shopify somehow linking the transactions together and flagging them despite having no discernable connection from what I could tell. The seller did not share credit info or anything of a sensitive nature, however sharing my email address and logistical order details with a person I don’t know seems like a privacy violation. Is this against any terms of service?