I suppose if my kid had some sort of compulsive wall-scribbling problem I might try my hand at some similar action. But hey, some graffiti is beautiful and vandalism effectively betrays certain dangerous sentiments floating around in the public sphere. They merit attention. Although I guess one could argue that if one riled up enough emotional attachment to one's city, its utter cleanliness would betray common sentiment too.
It's the classic "What if it happened to you?" stance. Still provokes some thought. Imagine coming home to a bedroom that looked like a public latrine.