I guess barefoot is best or the gymnasts would be wearing specialized footwear like most other sports. As a barefooted myself I would imagine with any kind of shoe you could not feel where exactly your foot is on the beam with any kind footwear, no instant feedback. They must have very strong feet. I am going to post this and look for a close up.
Maybe this kid is going to the Olympics 7-year-old sets Junior Olympics record in 1500 while running barefoot. Skandera posted a time of 5:08.52 to set a national age-group record and break the meet record by three seconds and did it without shoes. Daniel Skandera from Santa Rosa, Calif., is only 7-years-old and already holds the world record in the Mile for 5-year-olds, 6-year-olds ... "Skandera holds international records from distances ranging between 600m and 5,000m, along with two American youth records over the 1,500m. Most recently, Skandera ran a 4:53.40 mile at Cardinal Newman High School in Santa Rosa to set the international mile record for 10 year-olds. The runner has become famous for running his track races barefoot."