I'm certainly not defending the stone-throwing kids, just saying I understand the motive. I hope you understand the difference. As a bike rider, I'd be pissed if some kid threw rocks at me, and I'd probably try to club him with my U-lock, but I'd understand where he was coming from.
Also, I need to point out that USA Today isn't exactly what would be considered a scholarly resource.
ps, on the subject of bikes I'm selling a Jamis Coda city bike if anyone needs one...