my fiance has about 20 pairs of shoes (even by my own admission not that much) Most of them have been purchased in the past few years. We even got new closets so they fit in all nice. However, she also has a couple pairs of pink socks which are almost as old as I am. She got get in the sixth grade and still wears them and won't get any other pair.
They are really ratting, with some strings at the top (though no holes). I think it is strange that she has so many pairs of shoes on the outside (which everyone can see) but her socks are really old. Maybe it is that she takes comfort in them. Or maybe she thinks it is more important to look good for the outside world. (These socks rarely venture outside the house).