The purpose of saving my junk

It does not take long to fill your junk bag with all sorts of South Park reliqs, such as a Cartman or Ming CD - even sex toys and crack.

What I cant figure out, is wether to stash the junk in my toys trunk, or to keep it on me incase it could be needed for something - or even just vendor it.

Does the junk you find, serve any purpose besides being vendor trash?

Solution 1:

Junk is exactly as you described, vendor trash.

One reason for keeping it is for the achievement For the Horde. This requires you to not sell a single item (including junk) in a play-through.

If you've already sold some stuff though, not all is lost as there is the achievement, Junk Peddler, which requires you to sell 300 pieces of junk. And whilst you are at it, you may as well complete Make it Rain! (spend $500) as you will have a lot of cash to spend.

Solution 2:

None of the junk will ever be useful.