kWH is a more consumer-friendly unit since it's easier to calculate that a 100 Watt light bulb run for 10 hours consumes 1 kWH and you would just multiply by the cents-per-kilowatt-hour billing rate to find out how much it costs. If you were billed by the joule you'd need to divide by 3.6 times the rate. Or is it multiply by 3.6 divided by the rate? Do you subtract the 32 before or after?
Any consumer that knows that "k" means 1000 is going to know how to figure out how many seconds there are in an hour/day/year. There is endless confusion caused by the double use of time in kWh that this article is an example of. There is little doubt that using the base unit would be better.
