Celebrity guests on shows like "Survivor" are a great idea. Having their presence on these types of shows is an excellent marketing tool because people will want to tune in and watch what's going on and what will happen when something (good or bad, but particularly bad) happens to these big names.
Celebrities are known for their high class lifestyles with every luxury known to man, so seeing them struggling to survive in a harsh environment would be something I'd definitely watch. It would be interesting to see how they would respond to the challenges presented. Having to find things like food and water, something readily available to them, would be something everyone would struggle with, yes, but watching those who have everything end up with nothing would be great.
If one can define celebrity as a famous person, there are no better people to be made famous than those who participated in reality TV shows. The concept of being a celebrity requires one to be repetitively appearing in a non-reality movie, play or even a musical, which is not what reality shows require. So how then can the 'hero' in reality shows like 'Survivor' be made celebrities?
By promoting the heroes and the actors, rather than the shows, media outlets can help promote them as celebrities. This will make it easier for companies and franchises to feature them in serial advertisements, which is essentially how celebrities are created.
The ratings for the "Survivor" show would most likely benefit the show's ratings. It is fun to see celebrities get out of their usual routine and into something that challenges another aspect of their personality. Fans can enjoy watching their favorite celebrity pushing their limits and showing off their unknown skills.