I found out where all those socks go when you wash your clothes. I caught one escaping!
It was halfway in between the wash-barrel (is that what it's called?) and the outside wall of the washer, just the toe-end sticking out. I pulled it out, and I had no leftover socks that load.
I wonder how many socks are stuck in there, though, and if there's a way to get them out. Hmmmm....