Is it safe to use toe shoes in the gym?

Besides stubbing your toe, I don’t see any other disadvantages opposed to wearing gym shoes. As a layer of suede (on a tennis shoe)isn’t going to protect you anymore than a layer of stretch neoprene or whatever (on a toe shoe). Just make sure when or if you change your shoes at the gym you don’t step on the floor. Most people who wear traditional gym shoes wear socks which provide a barrier and absorb sweat from the foot. As someone who works at a gym as well as a podiatrist office, foot problems are no fun and very hard to get rid of if you continuously wear closed shoes. Athletes foot is not pleasant and can lead to toe nail fungus, which is super hard to get rid of. It would be good for you to spray your toe shoes with an anti fungal powder after your visit to the gym and around your exposed ankles before hand and make sure to wash your feet and ankles :0)