It's to do with the EPA rating. If the car maker allows auto start/stop to be turned off permanently then the ratings agency will test the car again with it tur

It's to do with the EPA rating. If the car maker allows auto start/stop to be turned off permanently then the ratings agency will test the car again with it turned off then combine the two results into their score. Having a slightly worse EPA mileage across their fleets is probably bad for sales and pleasing governments