I would never throw away a box from an Apple product, and tend to treat them almost as well as the computers/accessories themselves. In fact I have a garden shed - initially purchased for garden tools etc, but most of the large space has been taken up with original boxes & packing from Apple iMac G4's (they're large!), iBooks/PowerBooks/MacBooks/MBPros etc. Fortunately the 'little-lady' never goes in the shed, only I have the key......
If adding a new item to my collection, I always try to find one with the original box. I guess it could assist with a future sale, but like a closely-knit family I don't relish the thought of eventually parting with any of my 'siblings'.
It's unusual but I have occasionally bought an empty box for completeness, whether for a laptop or iPhone etc, but I'd only pay 'peanuts', as any spare box would have a serial number which didn't correlate to the item I hold.
Indeed some original boxes can be 'cherished' items in themselves. In particular I treasure the original box, accessories & packing of my Pismo and especially my clamshell iBook. And the contents of course!
Now, who can offer me a near-mint, boxed example of an early iPod classic.......?