Try loading and unloading your luggage rack and taking snowboards off the rack without running boards. If you stand in the door sills you get them all dirty and there's not enough width. In addition to the look, they actually provide a step for people getting in and out of the car, especially when adults back out of the car from the third row. Laslty, shorter people and kids depend on the side step to get in the car.
As for the nudge bar in the front, it's mostly for looks but it also provides a slight intimidiation factor for cars that try and jump in front of me. And I never get scratches on the bumper from cars/trucks with tow hitches parellel parking in front of my ride. I also hate being able to see all the stuff under the car from the side. I love both the mods, the complete the SUV look and all of the feedback has been positive.