I had a hip replacement four years back. I found that shoes restricted some movement when I walked. I wear sandals 100% of the time. When I teach, I have to 'dress' (normally, I'm a t-shirt, shorts and sandals kinda guy--mostly, I like to be comfortable (actually, I'm a natural slob)), so I wear black socks. Only time I wear shoes is for weddings, grads and funerals, and I wear boots for firefighting and rescue work.