The Beemer averages about 22-24 MPG during my daily commuting. It'll see the far side of 30 during freeway cruising, but my short commute involves two interstate merges (The Westland on-ramp to I-140 and then the I-140 to I-40 West cloverleaf) in only about nine miles of driving, which pulls the average down heavily. All this means that I burn about a gallon a day, and the size of the tank dictates a fill-up not quite every two weeks.
It's a little car, and it feels weird to watch it swallow $30 worth of midgrade, but I suppose things could be worse. $7.10/gal? Yikes!