A car that can only get the claimed & marketed mpg when under extremely controlled conditions is the problem.
When people are shopping for a fuel efficient car, they don’t realize that the car’s mpg is only for when the A/C is never run, radio off, tires over inflated, driven in a very bizarre fashion like applying power until the car reaches 65mph, then shifted into neutral, then coast down to 40mph, then power back on, never having to deal with traffic or other drivers.
Lets change the way these cars get their mpg rating. Lets give the cars to 10 completely random people in 5 very different areas of the country for 1 year. At the end of the year we average up the gas used vs the total miles. Then call this the “Real MPG” and make manufactures use that.
My Mother has a Honda Insight hybrid. When she drives it she never gets more than 37-38 mpg. When I drive it I can get 50 under the right conditions and average 42-45 mpg. She drives in a very conventional way, I have changed the way I drive the car to get the best use of the hybrid features.