The other odd thing I find odd about these cases is the curious absence of genuine offense. I remember watching the Justine Sacco thing unfold and noticing that nobody really seemed particularly upset - to the contrary, people seemed positively giddy about the whole thing. Very little "how dare she say that?" and quite a lot of "haha she's toast, isn't this terrific?".

In a way, I guess dogpiling on someone like that is probably a lot easier when you know nothing about them except the thing you're reacting to.