Actually reality TV is a good way of promoting anything. People like the prospect of personal rivalry and chemistry.
I guess this is also why F1 is so successful. It has over the past few years sold itself as a battle between a few fiercely competitive people. I think things really took off during the Mansell v Piquet days. Then there was the Senna v Prost, and then Senna v Mansell and Senna v Schumi, Schumi v Hill, Schumi v Villeneuve and Schumi v Hakkinen.
Now the interest is building up to see who can beat Schumi. And the general public is thirsty for any off track rivalries as well.
Other sports are no different.