Do you think Reality shows are scripted or not? ?

I think these shows are a bit crazy at times, yes. The more crap that happens though, the more I think they are scripted. I am sure millions of people try to sign up for Big Brother, for example. Yet, look who they have as contestants. For example, "Evel ".. He hob nobs (if thats the right saying, lol) with music stars and apparently a few actors. Or.. Will from seasons past ... he's a doctor? Why would they put someone who makes a lot of money on a show to compete to win a large amount of money? Why did HE win his season? It's gotta be scripted, the shows gotta be entertaining so people will watch.