What the boy did was certainly in poor taste but, aside from the trespass, I don't think it was criminal. There was no vandalism reported nor was anyone harmed or even threatened with harm. I doubt the boy was trying to make any philosophical point. He was just doing what 14-year-old boys have been doing for millenia. Unfortunately he ran a foul of a little known and rarelty used anti-desecration law. This prosecution is no better than the zero tolerance policies in the schools.
Freedom is an inherently offensive state of existence. No matter what you may believe, there will be someone who will ridicule it. Someone will burn a Koran, dip a Crucifix in urine, photoshop the Flying Spaghetti Monster into the creation image of the Sistine Chapel or use the word "citizen" (which is, apparently, banned in Seattle!) in a sentence. However, as HL Mencken wrote, "..the razor edge of ridicule is turned by the tough hide of truth."* If you really think what you believe is true then what is there to fear? Your pet theories or dogma will survive if truth is really on your side.
Silly attempts to limit offensive but otherwise peaceable behavior using law or speech codes is an example of the American ardor for substituting laws for common sense. The political Left, Right and Middle seem to share an insane belief that nirvana is just another regulation away. Wail all you want about Political Correctness but it is really just the Left's version of the anti-blasphemy laws.
* "On Truth" in Damn! A Book of Calumny. Page 43 in the Kindle edition I have. That essay is also the source for the title of this post.