This is another question that will get 50/50 answers, with none of them being wrong.
I usually keep my IN while not using, ONLY because it is in my driveway and when the slides are out, they are over grass on the 1 side. I cannot get to the grass under those slides when cutting, rather than closing and opening every grass cut, I choose to keep them closed.
I am plugged into a dedicated 50amp power source with the fridge on during camping season.
when I winterize in late October, they go IN and usually stay in till a few weeks before our 1st trip of the season...