Having seen more than a few broken toes and very bloody foot accidents as well as crew slipping in barefeet and hurting other body parts I have had NO problem with Captain and working crew wearing shoes and have required it off shore or underway after dark. Rare is the deck finish that gives any kind of grip to bare feet, -- teak works pretty good and Shannon Yachts have a great deck finish I never see any other manufacturer use.
***.Sperry makes a wide variety of good shoes leather and canvas, Harken shoes were always my favorite but are hard to find anymore.