They see a Chabad shul or library and they're afraid. VERY afraid. They know how they have nothing but disdain for other Jews to offer to their own, so they're afraid that some of their own may seek inspiration elsewhere. Often times that place may be Chabad. Just because your father is a hater doesn't mean you are, although I often am shocked to see how many of the zealots have kids who just as they do. I guess blood is thicker than water, after all. More and more of these haters are beginning to see the light, namely that they've been fed hate and lies all their life. The days of smashing windows, etc. are basically over, so they're left with late night spray-paint raids. How nice.