Dear Cecile:
This is in regards to one of your “recent classics” – “Why do you always see just one shoe by the side of the road? May 29, 1992”
A friend of mine in Seattle spent several years taking photographs of “lonely gloves”, after his woman-friend pointed out the ‘mysterious phenomenon’. (You’d be surprised at the variety of glove, location, and photographic background.)
He went on to exhibit an very artistic arrangement of his photo’s in the Seattle area. The exhibit’s title was “glove story” (and he had an associated website for some time, before moving on to other things).
Possibly the ‘lonely glove’ is easier to contemplate, and hypothesis the origin of, than that of shoes, but the upside is that they seem to be more common, and once you start looking you can be more easily ‘rewarded’ for your efforts. 
