Even if you have the box, how much is that item worth when you want to sell it anyway?  I do keep the box for some years but after that ... (?).  If we are talking about 5+ after, how much is it worth anyway.  And the talk of proprietary.  I guess if you have something that is still demanded like I have a Nikon film scanner despite that it is nearly 20yrs ago and Nikon have decommissioned all of them for 10yrs now, they still sell online for a decent amount.  Generally items don't attract such good prices.