Why is this legal? 3

Should it be legal to teach children how to vandalize our city? Isn't that carrying progressivism too far? Thanks to the NY Times's Bay Area Blog, we learn that the folks at 1000 Howard Street offer such classes:

We also offer graffiti classes, taught by local legends, to anyone with a passion for the urban arts. To check out our gallery showings, go to www.1amsf.com. We ship worldwide out of our store located at 1000 Howard Street, San Francisco, CA 94103. You can reach us at 415-861-5089 Wednesday through Sunday, 12-8pm (excluding Holidays).

They also sell the spray paint and markers to future and present vandals. They only offer the course to kids who are at least 14-years-old, but it's not clear why. Why not 13 or 12? Why not as soon as a child can hold a spray can? The city should shut this operation down and force them to defend their behavior in court.