Sheesh! If that's a crime, my son should be serving a life sentence!
Every day, on his way home from school, he cut behind a florist shop and brought me trashed flowers.
That is cool, that he loves/loved you so much.
Most kids just want you to co-sign minus the floral arrangements.
But there weren't thousands of him doing stuff like that, and probably he hadn't pissed off the local cops much. The Rainbow folks tend to think of their gatherings as "home" but the the local towns and cities, these people are like an alien invasion.
Suppose your son and a few thousand buddies had just rolled into town and started picking up things... it's a different picture.
Still, it doesn't justify 6 months in jail. A couple of days would be more like it.