Well see there's a difference. THAT type of live-action show contains heroes in sophisticated costumes with lots of martial arts action, which is very suitable for kids, especially boys. Reality shows are not. If I find reality shows boring, I can't imagine how bored a KID would be to watch one.
Also, CN did live-action shows and movies of their own and they sucked. Check out Re-Animated and Out Of Jimmy's Ass...I mean...Head.
I don't mind live-action shows being on Cartoon Network, but I think they should not only put GOOD live-action shows, but also stuff that fits the network (such as sci-fi and superhero) so that they won't totally Jump The Shark.