Alan,
It's not about conspiracy or paranoia, it's simply that some people are seeing obscured e-mail addresses in the text of messages, and other people are not.?This appears to be a 'feature' in the groups.io web view of messages and/or the summary message that goes out once per day (which is how I read the group messages). I suspect that people who get the group messages as separate e-mail messages see the intact e-mail address.
Ralph