Why do we have two Bank locations in each city?

Question

I.E. Thais has Suzy and Naji.

Why do we have two?

Answer 1

I think this is because orignally the bank was not located in the depot and had a different building, but later updates made a bank NPC in the DP for convenience.

In Update 8.5 Carlin, Thais, and Edron got updated looks as well as a few other areas which included adding the new bank npcs to the DP.

Answer 2

On Mainland, isn't Thais was the only city with two Bank NPCS?

NPC Naji  (located in Thais Depot) was introduced in the July 2009 when Thais was revamped. An assumption is that because of Thais being a popular city for players it is more of a Quality of Life change.