Hmmm, something may be wrong with your car; our 2.5 liter manual 2016 Mazda3 is also driven in a 50/50 mix environment of back roads and interstates; the rolling average is about 34 mpg.
I hope you're right. I really need to tear into this car once I get some more time. It hesitates a bit, and my long term fuel trims are in the negative high teens. I don't know why my PCM is pulling fuel like crazy. Already replaced upstream O2 sensor, MAF sensor, checked for the common MAF sensor wiring issues, blocked off purge valve line, etc. I haven't messed with the EGR or the PCV yet, those are next.
Do I drive the car a little on the aggressive side? Sure, but not so crazy that I'd be below 30MPG on a "normal" week.
Of course... no check engine codes at all.
'07 Mazda 3i
Previously driven by sensible wife, now being modded by gearhead husband. Uh oh...