Reality Show Competions: Chance of a Lifetime? Or Gimmick of the day?

Snake Handler David Weather Auditions For America's Got Talent.

America's Got Talent, So You Think You Can Dance, The Voice are just a few of the wildly successful brand of reality show competitions. My question is how effective are these shows in really giving the winning contestant a fighting chance at fame and career success. Looking at the history of past shows, it seems that the only contestants who've been catapulted into national fame and recognition have been past winners of Fox Network's hit reality singing competition American Idol. Past winners like Fantasia, Jordin Sparks, and Adam Lambert have released successful albums, and have managed to stay relevant throughout the years. Even past contestants such as Jennifer Hudson, who didn't win the competition, have experienced a high degree of success. So other than joining the American Idol machine, are any shows worth the exploitation of one's dreams in the hopes of manufacturing the next best thing? Seems to me the simple answer would be no. I'm not saying don't chase your dreams, but I am asking is it worth it now that singers are competing against....well...snake handlers. Say What??? 
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