The slaves/servants of the wealthy Romans actually lived very good lives. Probably much better than the average person living in a shack and working in the fields. Especially if you were a house servant. Which there might have been a dozen or more in a big house.
Slaves of the Romans working in Pompeii were more like indentured servants. These are not the same people building the aquiduct from the mountains down to Rome.
They also were not the same type of slave rowing a galley on the Med. Row well and live Juda Ben Hur.
Actually war galley rowers were more likely to be freeman like the skilled rowers in the vaunted Athenian navy. It’s not rowing a rowboat. It takes a great deal of skill to do it right and make the ship manueverable enough to be a weapon particularly a weapon that survives multiple collisions with the enemy. Athenian rowers weren’t of the upper class but writers of the day says they well knew their worth to Athens. You could tell them by the fact they always carried around their rowing bench cushion.