Granite has natural fissures which may make it more susceptible to cracking, but the fabricator should be able to pick this up. Cracking during installation is possible, but the fabricator would have to be pretty rough and negligent. The yarn about being glued to the cabinet tops is true, but it's usually a think bead caulk, which is pretty eash to break - the bigger issue is separating any slabs which have been epoxied together. There's no easy solution here. I suggest you fill the crack and live with it until you can't any longer, than replace the whole thing.