Mortgage companies typically require home insurance (and often pay it themselves from an escrow account so they can be sure it's up to date). It would surprise me if renter's insurance was generally required. Even if I have a nominal permanent address, I may not actually have a lease or spend much time there (if any).
The basic point is that most people in the US will want some permanent address where they can get mail etc. and is where they live from the perspective of official government documents. But they may not actually live there (and aren't required to).