If it's not too hot I don't think they're needed.Anything 88 or above it would at least be a good idea to bring a pair of sandals or water shoes and leave them in the locker.I went to Aquatica on one of Orlando's hottest days,possibly ever.About 97-99 degrees,sun all day,the wave pools had a thermometer that read 100 all day and my car's thermometer read 103 when I got in the car at 7 something,so I wonder what it read at 2-3pm.Up until 11am or so I was fine walking barefeet but by noon the floor was starting to feel like lava.I had been to waterparks countless times and while the floor did get very hot it never got to the point that I literally refused to walk out of a shaded spot as it meant walking at least 20 feet in totally uncovered cement that was probably 130 degrees,it was insane how hot it was,eventually I burned my feet and headed straight to the gift shop to buy a pair of sandals.I will say that not Blizzard Beach but Typhoon Lagoon is probably the most shaded waterpark ever and if there's a waterpark that allows you to walk barefeet without burning your feet Typhoon Lagoon would be it.