This is more of a vent(anger) than any information that you might need:
I let my brother/sister-in-law take my car this last weekend to a air show north of us in Oshkosh WI. It is about a four hour round trip drive and my brother-in-law has been very interested in the Camry Hybrid. So I thought I would be a nice guy and let them take it because they do not have a car that gets as good of milage.
I did my duty and ran through the operation of the car, especially the start and stop part. Off they went.
When they got back that night my brother-in-law asks me if the car has a feature that keeps the car cool when parked in the sun (that would be nice). I told him no it did not. And then it hit me, I asked him why and he proceded to tell me that when they got back into the car, after it sat for 5 HOURS it was nice and cool.
Yes, if you have not guessed it by now - he left the car on the entire time.

So now I have a tank of gas, that they filled up before they got to the air show, that is only 1/3 gone and the tank average is only 22 MPG.
This is going to really screw up all the hard work to eek out every mile for every ounce of gas. I will not even clear 30 MPG tank average by the time I am done with this tank.
So the moral is: if you let someone else drive your car make sure they know how to turn OFF and ON!!!