Yea usually its the edge of the fender as it lips back in that rubs the edge of the tire once its spaced out by the wheel.
I have seen a multitude of DIY involving everything from a bat, to pvc pipe, to a phone book lol. Bat is most common with a heat gun/hair dryer to soften the paint.
Or you can find a shop with a roller and pay to have it done. Either way, I'd want it done, if it rubs now... just imagine once you get all those hookers in the car. RUB CITY!!! lol.