@bear yes, interacting with a relay is bidirectional. When you add a relay, your instance does a follow, the relay then accepts that follow and follow's your instance back, and that starts all public activity going to the relay.
That is, you're consenting to receiving amplified content, and to being amplified to others.
@thisismissem Thank you!
I may turn those relays off when I find the accounts I want to follow.
Really enjoying ActivityPub and what it enables, so far.