Most of us are torn when we see people, especially younger people, expressing themselves artistically, when that expression comes in the form of slogans or pictures or completely confusing acronyms, permanently spray-painted or otherwise etched onto property not belonging to the artist. The preferred property is the back wall of a library, or a highway retaining wall.
How come no one ever buys his or her own house and then sprays stuff all over it?
We like to see people's talents come to full flower, and we also understand that everyone, most especially young people, wants to be sure that the world will take notice of their passage through this world. Back in Grandpa's day, some waggish youth would produce a #2 pencil and draw a schnozz posing overtop a wall, and that was daring stuff (left <<<).
Now, people arm themselves with 127 cans of Krylon spray and decorate the world in psychedelic fashion. This unfortunate Cyclops-with-a-spray-can is seen beautifying some unfortunate wall (above).
I just want everyone to know this is not new. It's been happening since prehistoric times (before someone said, "Wow! We gotta start writing this stuff down!") and here is one example. In a cave in Patagonia, Argentina, you can see where young men stenciled the outlines of their hands on the walls, and did some other redecorating (mainly with paint, although there is some evidence of a rudimentary form of wallpaper, and a rough attempt at vinyl siding on the outside.) No, but they did do some paintings that show the life of the hunters who passed by the "Cueva de los Manos" (The Cave of Hands.)
It has been estimated by scientists, and verified by Abe Vigoda, who was there, that these paintings were done between 13,000 and 9,500 years ago.
So it's really too late to say anything about it now.