we do not share your data with anyone and there are many ways to control the visibility and storage life of your data here.
but the internet is a public space and you should always assume your data could be compromised.
be smart with your password, use tor or a vpn, and use pgp for sensitive communications.
Imagine having a problem with your order and getting no reply for 5 days or longer. I wouldn't be very happy lol to answer your question some vendors reply same day some can go without replying for many days→