Sock Gnomes

I was having a conversation with one of my friends, and she brought up how her daughter is always missing socks, they disappear from the laundry, and you can never find a pair.
I shared with her that we have the same problem in our house, that even though I KNOW that we have enough socks to fill a laundry bin (because we have separated out our laundry a few times and discovered this fact) that we still can never find a matching pair, and often cannot even find two socks of the same color.
We have decided this is the fault of sock gnomes.
What else can explain the fact that a bin full of some hundreds of socks, disappears when you need them?
I have two grown boys living with me, ages @ 17 & @ 23. We all wear the same size sock, a men's sizes 6-12. When we moved into this house @ 3 years ago, we went threw and supposedly threw out all mis-matched pairs, and I bought several packages of the same style and color socks for each of us. In a ratio of about 1 in 4 black to white.
Today, none of us can find a single black sock, and most of the socks no longer match. They are different styles, different knits.
Once in a great while, one of the boy's baby socks appears.
Even though they never wore them here, and we supposedly threw them all out or gave them to Goodwill.
It has to be proof of sock gnomes. They must be trading up, giving us back the old socks they took in exchange for the newer ones.
I admit defeat.
I gave up wearing socks completely earlier this year.