If you would please indicate make model and year of RV you are asking the question about you will get more accurate answers to your question. Not RVs are the same in almost every area including this one.
That said, if your RV is receiving 120 volt power, don't put the shut off switches in shut off mode. Their purpose is to use when NOT on shore power, they remove almost all loads off the coach batteries and take almost all loads off the chassis battery. This allows the coach to sit for up to about 3-6 months and have enough charge left on the coach and chassis battery to resume using the coach without having to charge the batteries to start the coach and drive it.
On a newer Winnebago, with the coach shut off switch in the SHUT OFF position, the converter charger is not connected to the batteries. On a newer Winnebago, the step controller board is still connected to the Chassis Battery and the electric steps will still operate. It draws minimal power when coach door is shut.
Randy - Manhattan, Kansas
2015 Vista 27N
2016 Honda HR-V