As I get older I'm starting to realize that it's BOTH sides fault. If they ask you to leave and you do so, and they still fuck with you, then that's on them. But skaters, as much as we've been known to say "fuck authority", really need to step up and leave when asked. In such a hostile climate such as this, where skaters are getting shot, tazed, beat up, arrested, etc, it doesn't hurt to say "ok, we'll leave" and then come back at night or when nobody is around. Litigation plays a HUGE part in this as well. With everyone (at least in the US), ready to sue your ass for whatever reason they can find, it's not worth arguing about or making the situation escalate.