It all made sense as to why the Collectors were going around planets and star systems kidnapping the human population the moment I saw this. In Terminator Salvation, Skynet went around harvesting humans in order to skin them for their T-800 terminators. The Collectors were simply doing it on a much larger scale, for their supersized terminator.
The Alliance and/or Cerberus better have a plan for the security of Shepard’s mom.