So let me ask this.....  

I have  somebody ( mostly me) grind or buff  the tire surface with 36 grit sand paper, or a something similar during the week  and then wrap the tires to keep the tread surface from "oxidizing"  and then you remove the plastic on Saturday , you have clean fresh rubber. 

At one racetrack out here  they put down asphalt millings in the pits and people were concerned over  " the oil" in the millings affecting their tires