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.
There's always Reefer Madness. It's pretty damn funny, especially since it was released in 1936. Right up there with masturbation causing blindness and hairy palms. If that was true l would be wearing dark glasses, holding a tin cup begging for enough money to buy a new razor.
You shouldn't trust anything. If you want to mitigate your risk put your faith in wise judgment: make a smaller order, use bitcoins with escrow, use pgp encryption and go with a seller with history and solid reputation.