Through my years of tinkering with all types of things, I'd say it's probably very possible to paint them, but as with painting anything that's going to receive some abuse, it will take some serious experimenting before you find anything that will give you any sort of longevity. So I doubt it will be easy, I just wanted to play devil's advocate in response to all the people saying it's not possible.
Also, I'm new here, so feel free to take my opinion with a grain of salt, but I am a tinkerer, and I'm a firm believe in the "if there's a will there's a way" philosophy, but I also believe that even if there's a will, doesn't mean the way will always be easy.