Quote from the page it self:
"Ok, a few things about the bag....if you close one eye and put your open directly to the bag it looks dark, but them after a few minutes for me it was like looking into a black hole....all mysterious things started to appear...this may just be me or this bag may just hold the answers to the universe ( well with a little imagination)"
With 15 dollars I bet he could have bought some more acid.
on another note, I once got a can of Dr.Pepper which was only about 1/3 full from a vending machine...guess I should have gone to ebay..
PS: If you just barely open the tab so it hisses but does not pop open on a can of soda or (red bull) you can suck the contents out..I wonder if he did that for the red bull.