Lemmy has different pinning options. This post is pinned in “Community”. If you go to !newzealand, you should see it at the top.
Lemmy can also pin for local users, in this case any users on Lemmy.nz would see the post at the top of the Local and All feeds. I haven’t done this, as I find it annoying and suspect others would too.
Basically the idea is if you want to find it, it should be easy to find when going to that community page, but it shouldn’t be in your face all the time.