Locked threads
 

When I just searched for threads with 0 replies, a locked thread came up. This is pointless since no one can reply to it.

If you mean this thread, it is purely informational and doesn't require a reply. I'd guess it was locked to prevent it turning into a discussion

May be you can treat it as a "Read-Only" thread.

Most of the time locked threads will have replies so its rare they'll show up in the list. Most of the time it is an informational thread, Jeremy might have an announcement, etc. But if its a thread that gets closed cause its a double post, usually there are no 0 replies on those as we reply to tell the user they double posted, rules, etc.

If such threads are intended to be informational then why doesn't Jeremy link to them in the email newsletter we all get on purpose? If they're that important then think how often members that log in rarely will ever see them. Some people never see these threads and I think it's a big problem.

The "Informative" threads, as I have seen, are generally the first few threads in any forum, and easily noticed.

They won't get noticed if people aren't logged in and online to see them you know.