Ron,
The refrigerator is not different from the microwave or TV, they are plugged into inverter feed circuits also. The reason that your residential refrigerator needs to be plugged into an inverter powered circuit is so that it will have power when you are not on shore power or have the generator running, like when you are driving or when you spend an occasional night dry camping when traveling. When you are on shore power or have the generator running, it does not matter which circuit it is plugged into because all circuits are powered equally, but when you are not, only the inverter feed circuits have power.
Gerald