Why were slaves in ancient Rome treated the same as things?

Because slaves at that time were property and were sold for money. In addition, the slaves had no rights, which caused their humiliated position in society. True, constant oppression and infringement became the reason for frequent demonstrations of slaves. One of the most famous slave uprisings was the uprising of Spartacus in 74 BC. Then Rome was under great threat, as the slaves managed to collect a large army.