Reality shows have had a big rise to being common place on TV screens, inevitably there are hiccups in that rise. Calling the people involved "star talent" is incredibly ironic given they have no talent, but MTV should use lots of discretion. They not only want the right people, but those who are mentally stable and not being taken advantage of.
I'm not against the genre of reality shows, I find myself watching them sometimes. I do think MTV could use more discretion when picking the cast. Reality shows can be both entertaining and a bit educational without losing ratings. It might take a bit more effort, but I think there is a large audience who would actively watch more interesting and thought-provoking reality shows.
Reality TV is the lowest common denominator of television programming. The people who enjoy these kinds of shows have no standards when it comes to the "stars" they worship. The more drama surrounding a show and it's cast, the more the audience will lap it up. I say give them what they want as long as it keeps them quiet.
It is not necessarily imperative for MTV to exercise a great deal of discretion when it comes to choosing their reality stars as their shows are so cheap to make and so easy to cancel. While the participants might prove themselves to be volatile on camera, it is unlikely that this concerns MTV who thrive on sensationalist entertainment.