I think that video shows us that structures on the Eastern part of the United States aren't really made in mind for earthquakes, not the ferocity of the quake. Those cars getting smashed was more an act of gravity, methinks
However, out here on the West coast I get the feeling people don't think much of < 6.0 earthquakes (or maybe that's just the people I know, since my knowledge is not representative of the whole West coast). Actually, most of the West coast (or the West coast of all the Americas) lies on fault lines. From my knowledge, not all of the energy released from an earthquake can efficiently travel between different tectonic plates, but since you guys are out on the expanse of the North American plate, the waves released should travel much more efficiently, therefore, farther. So I guess it makes sense people from numerous different states felt it.