If the wheels are OEM, then the fact that the tires are over an inch wider than stock probably explains why they seem to stick out further in the front. Maybe the stock tires were recessed more than the fronts and therefore had a larger margin for a larger tire without seeming to stick out.

 

If you look at your door tag, 245/75R16 should be the OEM tire size. 275s are an inch wider, and are going to negatively impact mileage since you have a larger footprint of rubber, meaning more friction and rolling resistance.

Wider tires are better for offroading, but worse on pavement.