Garzie, I don't think I saw the thread you mentioned. Was it a new thread? Or, a new user replying to one that was already established? A non-moderator can only delete their own comments. If they started a new thread and there were no replies to it, then deleting their comment, of course, would delete the thread.
I did see the one RainyCloud mentioned. In this case, it was an established thread that a new user bumped by replying to it and asking about
where to buy a Spooky2. I found the link in my browser history:
https://www.healingwell.com/community/default.aspx?f=30&m=4278091&p=2. As you can see, the thread still exists, only the recent comment that had bumped the post to the top is now missing. It was right after the post by user "wavepruner" on Page 2.