Ok, three women in my life like to wipe dust/dirt off my black XF with their hand. As we ALL know, this will leave scratches in the paint. Now, all three of these women will take their car through a car wash, maybe 3-4 times a year, tops. I have asked them, ( in the nicest way possible) to please stop doing that. They all give me the same look. The. "I can't believe you're so fussy about your car" look. Any suggestions?