Complaint Review: enterprise car rental

Upon returning a rental car to Enterprise, I was charged a $75.00 fee to detail the car. When I asked why the fee, I was told because the car smelled of cigarette smoke. There is nothing in in the rental agreement that states "NO SMOKING" nor is there any sign or other wise that forbids smoking. Futhermore detailing is a cleaning process not a deodorizing process. I am being penalized for the managers personal dislike of smokers. Since there were no stipulations about smoking in the vehicle or in the contract, I feel as though I am being wrongfully charged.  Please return the $75.00 to my account.