The entertainment value of these type of performance contest shows IS that hope though, right? That "if someone will just listen, just notice then they'll see that I'm really special!" That's why people watch, to see if there IS a Cinderella story here, or if there is a train wreck to be seen.
Few make it to popular success, but the fact that anyone does means it is possible, and the ones with the 'do or die' attitude at least are sticking with their dream. We want to believe; that is what drives the audiences for these shows.