Cockfighting is illegal in Vietnam but you seem them all the time. There are at least 1 cockfight near my current alleyway each day now, or so it seems. They are not as violent as the ones you see in other parts of the world but both fighting roosters are still trying to kill each other (I have seen violent cockfights near my last house in the Phu Nhuan District with a lot of blood). Police are very aware of it, how can you miss the rooster basket cages outside of the houses? In general, animals are treated quite poorly in Vietnam though there are more and more people here that are starting to take notice.
Cockfighting is quite common so it is not surprise that most people just do not notice. Hopefully the police will stop this act of cruelty.