Why are so many people clean? They shower, deodorize and add scents. It wasn't always so. I think the reason is to conceal information about ourselves. Most of us now live in cities and complexly interact with strangers. We don't want them to know what the pores and glands on our body advertise about sexual status, how hard we exert ourselves and the food we have access to. (Think farts). We hide our stools (flushing is the modern way).