5 Estate NPCs?

Quick question, because I couldn't find the answer anywhere.

In the 3.1 patch notes, it's mentioned that, with the addition of the Estate Steward, the number of estate NPCs allowed will be raised by one for each house size, which brings the number of NPCs for a Large plot to 5.

Now, I'm aware of only 4 types of Vendors: Junkmonger, Material Supplier, Mender, and the new Steward.

What would be the point in have 2 copies of any one of those? Or am I missing a 5th type?

I seem to recall they added (or were supposed to add?) a fishing bait vendor, but was that for Estates, or for Residential Quarters?

Thanks in advance.

Probably added for future expansion of NPCs, they don't currently have 5 types.

This is how it was pre-patch as well. There were only 3 types of NPCs, but you could have up to 4 in your house. I guess it's for people who want more NPCs as decorations, or maybe they want a particularly useful NPC available on multiple floors.