User blog comment:CrimsonShogun/Omega DLC (and Nyreen!)/@comment-4973403-20121112183951/@comment-2250460-20121114022542

You're making one big assumption though: That all those millions of people are still alive.

So far Omega has been through a Zombie Apocalypse (of sorts), a Cerberus War, and Now a Reaper Invasion, all within months of each other. I don't think there are that many people besides Cerberus Operatives on Omega.