This is an excellent opportunity for the community to practice not having a police department. Why rely on the NYPD? Just get some other adults together and go straighten those kids out. They’re just teenagers, right? Head over to where they’re putting on a display and in firm voice let them know that they have to give you the fireworks, or you are going to go talk to their parents. I’m sure that they will comply and apologize, or blow your brain out.