Gold - Kingsmarch tresury vs my pocket

Why is there a distinction?

What value does it add??? Was it supposed to be fun?

This is the umpteenth time I had to re-do a trade, because I did not have the 250 gold required to set it up, and I had to take it out of Kingsmarch. It's a waste of time (not nearly as bad as the old trade system, but still a waste of time).

It is for that purpouse. That exackly thing is very important while learning about managing finances.

Don't you usually carry several millions in your pocket? Cause I do

Usually i go with few millions to work.
When i´m done with work I have no money left.
Next day same thing. Wait... Don´t you are all billionaires?