I have a 2008 Yaris and I seldom get less than 40 mpg. Most of those less than 40 mpg tanks occurred on long highway trips against a really adverse headwind.
The less you use your brakes, the better your gas mileage will be. With practice, you too can spot red lights from as far as a quarter mile away and coast towards them instead of continuing at your normal speed only to stop at the last second, coming to a complete stop only to have the light turn green right after you stop, had you coasted, you would not have reached the light early enough to have to stop and you would just have resumed your speed. Less energy expended approaching the light and less energy expended to re-accelerate the car.
As a side benefit, after 110,000 miles, my OEM brake pads still have over 60% of their lining left.