My cats do the same thing. A couple of neighborhood cats (no one knows who they belong to) come up on my patio sometimes to groom, sometimes to spray. Well, my cats have been pretty good about not peeing anywhere but since those other cats started coming around, Yodie started peeing again, so I had to increase her dosage of Clomicalm. People just don't realize the problems they cause when they're irresponsible pet owners, problems not only for their dear animals but for the rest of us, too.