Frenzied "Flutterby"

When I watered flowers early this morning I got my sneakers wet, so I put then on the sidewalk to dry in the sun. I noticed that an Eastern Swallowtail butterfly landed on them and rested there.
Later when my wife and I went out to drink coffee on the porch, I grabbed the shoes and put them inside. As we sat there we noticed this very frenzied butterfly darting back and forth were my shoes had been. A couple of times it came and circled over my head for several seconds. We finally realized it was looking for my shoes.
I put them back out on the sidewalk and it landed on them and stayed there until I got the camera and took some pictures and we finished our coffee.
I'm not sure what attraction the shoes had, but the incident made a pleasant morning distraction.