i feel the same way. i have no issues keeping up with traffic in regular mode and am getting 42+mpg. heck, i feel i can have plenty of fun in regular mode.If I'm thinking about it and feel sprited, I'll hit sport. But if I'm on the way to work thinking about other things or just sort of tooling around, I leave it in default eco mode. No point in lower gas mileage ( for me 2 ish less in sport) for no reason. I used to think I wanted default sport mode, but now I'm thinking they did it right. If I want to drive sprited I can choose to, otherwise, save the gas.
I am generally in eco mode though sometimes in sport as I call for it, as noted above. My B trip odometer is now reading 34.6 mpg average over 2,300 miles of mixed driving, biased toward local roads and mixed terrain. I disagree with your assumption that sport mode does not impact fuel usage. The accelerator and engine operate more aggressively at all times in sport mode and results in lower fuel mileage IMO. I do agree being in sport mode affects the way you drive and further adds to the fuel mileage degradation-and the fun.I always drive my PE in Sport mode and find it unsafe to drive it otherwise. I seem to stall it a lot in the the economy mode since I am use to the more responsive throttle.
I don't believe the mode has anything to do with fuel mileage. How you drive it has a lot to do with fuel mileage.
In 4000 miles I have never gotten better than 31 MPG