Crew on a ship require 1 gold every X hours. (X depends ship's level of accommodation and what you assign them to) So if you have a crew member on a cannon, they might require 1 gold every 1.2 hours. If you assign them to nothing that would double to 1 gold every 2.4 hours.
On a galleon running 60 crew members that adds up A LOT. So when you park the ship overnight to log out you have to go through and unseat every crewmember one at a time... again... 60 crew. That's annoying. But then the next day before you can take your ship out you need to reassign every single crew member to every position and THAT is an absolute nightmare.
But the amount of gold you save by doing this makes it almost necessary.
What we need is a way to hold E on our ship, unseat all crew members at once, then be able to hold E again and put them all back on their last assignment assuming they havent been reassigned manually since.