A long time ago, the Zebucarts in Liberty would mine Neural Keysyncs, and then sell them at the AI base. They still mine the Neural Keysyncs, but they no longer seem to be able to scoop them (or sell them), leaving them floating around as debris.

I always found it cool to kill them occasionally for 50mil or something. I don't see why it should be left the way it is, in a confusing an non-functioning manner.