I guess "show filtered" is more like "allow filtered to be shown", so whether or not the filtered items themselves are shown depends on whether or not you're showing that spawn type. That is interesting. It seems odd, but it sort of makes sense to me.

And no, I wouldn't expect them to show in the spawnlist if they're filtered. I meant if you removed them from filtered and just toggled showing/hiding them on the map, then they'd show up in the spawn list.