The first post is always the same because it's literally the "Thursgay Opening Ceremony.swf". It's a signal and a reminder that Thursgay has begun.
The rest of the Thursgay threads are not duplicates of the previous week. I usually try to post flashes that haven't been posted in a while.
And I really don't understand crying over threads getting pruned on /f/ of all places. This board has slowed down so much that threads stay up two full days on average. And you want to slow it down even more?