I've never actually seen a cockfight. I think it's really adrenaline-filled and I might enjoy it. I don't like violence, but I think it's compelling.
Let's remember that violent encounters have always appealed to mankind, from Roman times with gladiators to the present day with martial arts, boxing, and MMA.
I don't think it's strictly related to addiction; gambling in general is addictive, so cockfights are just one of the many bets you can place.
There is a very big difference between Rooster fights and MMA fights (or any other fights that take place in a closed arena, like boxing).The thing is that cockfights are held by their organizers and they force the roosters to fight each other. Although these are animals that need to fight only to find out who is the best male for the hens.
I want to say that Roosters are just animals, they have no will of their own and are made by people to fight. While MMA fighters go to the ring of their own free will to earn money or get fame.