Maybe those reasons are just as arbitrary as racewalking's ban on technology... because the goal isn't to keep your feet on the ground - it's to see who's fastest doing a funny walk, just like triple jump is to see who can go the farthest doing a funny jump, hurdles are to see who can run the fastest with plastic barriers in the way, and tennis is to see who can hit a ball over a net the best, but only within certain carefully drawn lines and with a racquet and not a paddle or hands or feet.