Especially as many of these individuals are recent graduates so likely have student loans, won't have had any time to save, are on the other side of the country

Especially as many of these individuals are recent graduates so likely have student loans, won't have had any time to save, are on the other side of the country from any previous support networks etc. There's also the potential, or at least perceived, resume / CV impact of quitting your first job after a short period. The right answer might be "just leave", and clearly many people do just that. But for many they won't or think they can't - so companies cannot assume that just because people stick around that things are good.