Why don't all electrical plugs work on inverter only??

My understanding is that outlets by the bed are not wired into the inverter for safety reasons. If you have necessary medical equipment plugged into a bedside outlet and the battery runs down then you lose the use of the equipment. To insure an uninterrupted power supply you must have your generator running or plugged into shore power for those outlets to work.

I just ran an extension cord from an inverter supplied outlet to bedside.