Looks like Subarus are also defective. More excerpts from my owners manual:

Salt, chemicals, insects, tar, soot, tree sap, and bird droppings should be washed off by using a light detergent, as required. If you use a light detergent, make certain that it is a neutral detergent. Do not use strong soap or chemical detergents. All cleaning agents should be promptly flushed from the surface and not allowed to dry there. Rinse the vehicle thoroughly with plenty of lukewarm water. Wipe the remaining water off with a chamois or soft cloth. Wear rubber gloves and use a hand brush when washing down underbody, inner fenders and suspension to effec- tively remove mud and dirt off.

What kind of a shitty automaker would require such care after just some tar or bird droppings!

As expected, cars need washing.