I don't understand your numbers. How is Rav4 going to save you $2000 a year over 4Runner?I agree, if it's marked up $7,000 I'm not getting it. Not yet anyway. But for me, in my state, and buying at list price, it's maybe $1,500 more. Not so unreasonable for a cool car.
One of the odd things about comparing any car that (already) gets good mileage is that there is sort of a point of diminishing returns. It's one thing to go from a 4Runner to a RAV4. The RAV4 will save you $2,000/year, even if you only drive 12,000 miles. But going from 40mpg to 50 mpg only saves $240/year. And going from 50 mpg to 60mpg saves $160/year. So from a purely $$$ perspective, what's the point. On the other hand, electric mode has about 1/2 the pollution of gas mode. So there's that.
Some other car (12k miles / 50 mpg) * $3 per gallon = $720 (Saves $180)
Rav4 (12k miles / 40 mpg) * $3 per gallon = $900 (Saves $1100)
4Runner (12k miles / 18 mpg) * $3 per gallon = $2000