I have several small wooden coffers full of dice, as well as one vault* and several bags for games. Very, very few complete sets in there.
Back in the late 80s/90s I inherited an odd position in one frequent group about dice - not caring about complete sets. So I was never the one going "hey, did anyone pick up my jade d20" at the end of a game. What started happening was that if there were dice left over after a game that no one claimed, they'd toss them to me. And if next session someone was "I'm missing a firey d8" I'd pull one out and give it to them. But then it got to the point where people would lose a die from a set (often with some other group), replace the set, and just give me the rest. I guess because I always gave people dice to complete their sets instead of protecting my own (except that one Torg d20 - which I still have).
Combine that with liking dice and picking up odd ones here and there, and I ended up with way more dice than I can carry to games. Just length of time collecting.
Now when I'm running to teach people how to play I give them dice - usually complete sets - to get them started. Them having their own dice is more joy then those dice sitting in my horde.
Oh, I mentioned "vault" earlier. It's a black textured plastic box about 10" x 6" x 1.5" with a puzzle lock. In reality it a amazingly sturdy Betamax tape case that just happens to look nice and have a lock that requires multiple movements to open that seems to confound people who do not realize the instructions are embedded in the plastic.