Having multiple outlets on the same breaker is fine as the house wiring will work fine with the trip current of the breaker, and it even might get inspected during installation to make sure it was sized correctly (this varies highly by location and the amount of change&#x2F;new construction).<p>The cheap non-fused extension cord someone is using for both their microwave and toaster oven typically cannot safely handle the over current until the breaker trips like the house wiring can.