Weird pipe in the trunk

So let me get this straight... the 4 vent lines from the top of the tank go into the metal vent tube in the trunk area.. then there's another long line that goes from the vent tube all the way up to the engine compartment, and gets plumbed into the PCV system at the valve cover? So what if I'm running no PCV system?

Why wouldn't you be running a pcv on your car?
The crankcase needs to vent or else it will blow out your gaskets, usually the valve covers.......