Since most of the day to day work was carried out by Slaves and foreigners in Ancient Rome, this meant the mass populous, the poor classes of Romans, the great unwashed had nothing to do. Well except eat their bread dole, go to the baths to wash and gossip and of course attend the games.
The games had started as a religious ritual at funerals but by the time of the emperors they was held ten to twelve times a year and their main function was to keep the poor and unemployed entertained.
Over time, the games became more spectacular and elaborate as emperors felt compelled to outdo the previous year's competitions. The games involved more gladiators, wild animals, occurred more frequently, and became more expensive and more outlandish.
In Rome the gladiatorial games were held in a huge amphitheater called the coliseum. This huge stadium opened by Titus in 80 AD was situated in the center of the city stood 12 stories high and could hold 50,000 spectators.
Like many modern professional sports stadiums, the Coliseum had box seats for the wealthy and powerful. The upper level was reserved for the commoners. Under the floor of the Coliseum was a labyrinth of rooms, hallways, and cages where weapons were stored and animals and gladiators waited for their turn to perform.
Some gladiatorial contests included animals such as bears, rhinos, tigers, elephants, and giraffes. Most often, hungry animals fought other hungry animals.
The Circus Maximus
Romans loved chariot races, which were held on special racetracks called circuses. The most famous circus, which was in Rome just below Palatine hill, was the Circus Maximus. In chariot races, two- or four-horse chariots ran seven laps totaling anywhere from three to five miles.
The Romans supported various factions such as the Blues or the Reds much in the same way modern people support a famous football team. This rivalry sometimes over flowed into violence and many were killed during riots.
As the Roman Empire started its decline, the author Juvenal (55-127 A.D.) noted, "The people are only anxious for two things: bread and circuses."
The most popular game in ancient Rome was chariot racing. It was so popular that bigger and bigger stadiums had to be built. The Circus Maximus in Rome overlooked by the Palatine Hill (Where the Emperors lived) was massive and dwarfed even the the Coliseum and could hold 350,000 spectators. The above clip is from the chariot race in Ben Hur which gives an idea of the spectacle and grandeur of the games and chariot racing in particular. This race was set in the Roman hippodrome in Jerusalem.