You have seen the commercial advertisements for one of the anti-fungal where the media wrongfully portrays dermatophytes as a bacteria/animal type of bug with legs and arms with a mean looking face madly scurrying about. These are not bugs but a fungus that can be spread in many forms since many take on different forms from a seed type to a slime type and all are unseen to the naked eye that are causing fungal infections.
Unbeknownst to many the cause of many fungal infect of their feet is due to exposure to gyms. It is never a good idea to be bare foot in an area common to exposure to people that have such fungal infections.
Any member of a gym that is known to have such an infection should take safety precautions to minimize the risk to others.