User blog comment:The Milkman/Reaper Logic/@comment-5030041-20120425001034/@comment-5124423-20120521164517

I absolutely agree on your point. The Reapers do not want to wipe everything out. They just harvest advanced evolutions that have reached their pinnacle of evolution and might now become a danger to the rest of organic life due to their creations. If the high advanced species create synthetics that can overwhelm and kill them, why would they stop to kill all organic life in the galaxy. The Reapers prevent that from happening as they just store the advanced civilizations, leaving those behind that cannot create dangerous synthetics (yet).