Pit fighting

Although the Grand Arenas no longer exist, the tales surrounding them are abundant. Elders speak often, and fondly, of them despite the oldest of them being too young to truly remember what it was like. Once they have drunk too much, they often tell stories of blood, and of the large and noisy crowds. Foreign creatures and monsters that are unseen today were brought together, to kill for their amusement. 
Criminals and prisoners were thrown into the mix alike, the blood spilled thrilling the crowds and bringing a fervor people today just don't have. But it was the heroes of the pits that people truly loved. These legendary fighters would dance between all that was thrown against them, and the people would lose their voices screaming those names.
Pit fighting has remained a staple of societal decay, and has grown more popular over the years. Without the majestic beasts, those who wish to continue this tradition instead choose certain animals to perform these vile acts. Roosters, dogs, and in some cases, crabs are raised with this as their sole purpose, their only value ascertained from how many innocents they can kill, and how easy they are to control.
While the peak of the Grand Arenas and pit fighting was wicked, there was class to it. The lowbrow enjoyment found among the dregs is not limited to animals only. Urchins and criminals are made to kill one another, and beggars are forced into these pits to fend off against the teeth of rabid beasts.
The cruelty shown denotes bestial, almost unforgivable nature, for those who are forced to fight are often barely worse than those who jeer at them, and whip stones at them. The unspoken truth is that any of those could be the next one in the pit, forced to kill just for an unsatisfying meal.