@Aditya very good narration.
When we talk about a tradition, we need to analyse few of the reasons behind it. We have no habit of documenting our practices in olden days. Even if it was documented, they may not be saved. We have been using turmeric for a longer time, without knowing that acts as an antibiotic. The same way, this Jallikattu may be continuing to happen without knowing it's purpose.
Before talking about the purpose, I would like to clear few things, I watched Jallikattu from the place it happens. It is not true that, the bull are tortured as mentioned by Natrajan sir. Many organisations, who purposely wanted to stop Jallikattu, have created those scenes and broadcast the same with the help of media.
True Jallikattu is, the bull will be freed from one entrance, run to certain distance. In that short distance, whoever held the bull for 3 feet will be considered as winners and given prizes. Bull will be given prize, if it did not let any one to touch it. The bull will be given higher rank, if it stands in middle of that distance and rotate for once or more than once.
In olden days, the winner bull is known as breeding bull. With these games, they find the best bull to breed. Even now, in rural areas, these games are conducted for same reason and not just for bringing injuries to any. Like many other games, it needs to be regulated and not to be stopped.