The lesson here is to look for ways not to buy the DVDs in the first place but to borrow them from the library or the DVD shop or online, or create a group and share the DVD amongst yourselves or be really selective about the number of movies you watch and choose a game of cards or conversation around the fire instead.  

For now, giving the DVDs away puts them back in the system, allows others to benefit from something that otherwise would just sit on my shelf, taking up space and requiring an extra packing box every time we move house and that feels good.