Why electric company sell the electricity according to real power?
It takes centuries to many many decades to change standards in the power industry.   It was a Westinghouse electrician, who designed the original meters in 1888 and it measured only current, then voltage was added and the meters were refined and reduced in size.  I believe it was seen that VAR meters were inaccurate with non-linear loads, varying voltage, power factors and the penalty for VAR readings were too high.  So true watt-meters were demanded.

Meter design is still evolving but they must be amortized over a 50 yr expected lifespan.  Changing consumer rates and method of measurement is a highly political topic as energy costs and votes and often related.

Economy of scale might indicate that the consumer costs might not be lower if responsible for power factor correction, but new regulations on high PFC power supplies is one way of improving PF with the rise of SMPS.

Now with utilization losses from poor PF being more significant opportunities for improvement, utilities must offer incentives, either by rate structure , penalties to motivate customer change and consider the active VA correction technology to improve efficiency against costs of new generation.