Note: The role of a U.N.S. battleplate has long been that of "mobile fortress," complete with housing for soldiers, officers, technicians, contractors, and their dependents. After all, these great ships were quite literally the safest places you could be, so why would you want to live anywhere else?

With the advent of the teraport, it became obvious that these fortresses might get placed on the front lines, and their internal structures were modified so that civilian and dependent quarters, as well as a number of other facilities, could be "parked" in Sol System while the battleplate proper, with all its attendant shooty bits, sailed off into harm's way. 

It is still a tragedy on an almost unimaginable scale when one of these vessels is lost, but the modern, post-teraport configuration means that those left behind are numerous enough to set a world on fire when they march forth with torches and pitchforks.