I think it also confuses flies who like to land on dark patches. It might make it harder for them to alight on the Zebra and that would be a huge plus. Other animals don't have it because they'd stand out a mile and might be using the quiet approach to survival. Like a shop advertising we have CCTV, they're not trying to catch thieves just sent them elsewhere. Maybe the Zebra is doing something similiar. All they're short is the two flashing yellow beacons saying "don't cross me".