Riding barefoot or in sandals is a bad idea. Why? I used to think it was alright, you know, just down to the beach or whatever. One day I am doing a casual slow ride on an MUP with a friend. Out of nowhere, as I passed a family, the dog lunged out and clamped down on my foot. What kind of dog? Pit bull. She was wearing open toe sandals, I had cycling shoes on as I clip in to all of my bikes. I am glad that it was me and not her that was attacked. After that day, I swore that I would never wear anything but appropriate footwear while riding. To this day, I swear I can still feel the heat of that dogs mouth on my left foot. Luckily the family managed to pull the dog off before any real damage was done.