I see more of what you mean.
Well I think what gets these different entrepreneurs on shows such as The Big Idea, is that they either promoting something, or they just have a unique story.
The last show of his I watched talked with a mother who took her children to a church event that had these inflatable slides and bouncing rooms. There were other games and activities in the area but all the kids just wanted to wait in line to use these toys.
So then she decided she would want to start her own business that had nothing but these toys for kids to play on.
That is a unique story. It is also an inspirational story. It inspires other stay at home moms that they can indeed start a business if they have an idea.
Sam Walton was another amazing amazing story. Read any book on him and he will no doubt inspire you.
So to ultimately answer your question, I'd say you just have to either be successful, be promoting something, or have an inspiring story.
Would you like to be on tv to tell your story?