Sorry for the delay posting/commenting. I had trips to the theatre to first aid at Les Miserables on Wednesday night and then to see Rocky Horror Show as a paying audience member on Thursday, so a few late nights this week!
I feel like this is the top of a shoe or some fabric that is designed to let something breathe. Like a sneaker. Or some stretch elastic that holds on the back of a seat or side of a bag. I will stick with sneaker though.