Nobody has robbed a bitcoin exchange yet, I assume they have insurance since most are not in secure offices.
they operate only online i think, they have not a real physical place, like bank has, their cold storage, are probably well hidden somewhere underground and in a different location( in the case they have some small office)
but they are still targeted by hackers , which is vastly worse, then a real thief
Yeah absolutely right. Like what you said. Different type of material currency has different ways to rob so has different kinds of robbers. And the more IT involves in, the more risks it is.