I admire the skill and the amusement factor.
Funnily enough, though, while I have very little time for wank on "gender differences" (other than purely physical averages), this drawing cock-and-balls thing is really the most significant gender difference that I can think of. I've never seen a women draw random vaginas as grafitti. (Ok, there's the almost-always-appalling "yoni" art, but that's not random grafitti.)