This is a random question, but I signed up for an informational meeting through zoom with a local doctor. When the invite was sent, it included everyone's e-mail address. I was very surprised. Is this normal protocol? I've never been to one of these meetings before.

it is for Zoom meeting invites, yes - and I don't know if there's a way to "hide" those (if you don't want the other participants to know everyone's email address). I've never had a health-related Zoom meeting (unless it's just me and my PCP), so I've never come across the issue