Totalizers and compensated metering are two different things you can have both or either without the other. As indicated by others, compensation is used to account for transformer losses when the service is on the high voltage side and metering is on the low voltage (cheaper voltage transformers). Totalizing is used where you have two meters for some reason but are billed on the basis of total load. It is particularly useful for demand metering where if you just add two demands (peak loads) together, you will get a higher value than the total demand. This is because the two demands are at different times.