Marriage is hard. It takes a lot of work to survive any type of relationship. Having all of your dirty laundry aired on reality television for millions of people to watch is a recipe for the failure of that relationship. What happens in a relationship should stay between the two people in the relationship.
The presence of a film crew and the need for often dramatic stories for television reality shows means that what happens isn't really reality any more. When romance is the subject, a showbiz setting can distort the feelings and perceptions of the people being filmed, and teach them that their behaviour is appropriate because it receives a positive rating. While relationships and marriages which take place on reality television are not destined for divorce, it can create a false experience for the couple involved, and promote bad values for viewers, all in the name of good ratings.
Reality television marriages a not setup for reality television divorces. It is merely a ratings grab - nothing more and nothing less. However, if ratings are to be had from watching said marriages disintegrate, then the first people in line to capitalize will be production companies. It would not be the first time they use other people's misery for profit.
Even though I do think that reality tv marriages are a sham, I do not think that the producers would think that reality divorces would make for a successful program. Most viewers of these types of dating and marrying shows, are simple minded individuals who are interested in seeing the love connection. I do not think they would be very interested in divorce tv.