I would definitely purchase a bunch if they were cheap enough if you have them in hand right now...
Thing is, there was at least one angry user threatening to tag me as scammer if I should dump or re-sell the chips he paid for. Obviously he is right, I am not allowed to do so without permission.
That's why I asked if someone knows where my liability period ends. Obviously I can't keep chips and all order data active for years, at the same time - and to prevent recourse claims - I need to keep them and wait until they become folly worthless
You could make a mosaic with them, frame it and hang it on a wall. As proof for an enthralling anecdote you can tell your grandchildren one day 
Yes, since they are already in trays, that's maybe the bast I could do with them.