Some people is going around with no socks during Summer. Of course mine is a "self-sponsoring" suggestion, but I can tell it is not so healty, special if you don't know where your shoes are coming from and how they were produced and treated.
At least you can wear the "ghost" socks, kind of ped you can wear inside the shoe and not visible.
Those will protect you and let your skin breath.
Not to be mentioned that for elegance issues, of course, always better to wear socks, unless you are sailing or walking on the beach.