Why were the majority of southerners pro slavery?

Understand that slaves were the same as money or cattle or crops. They were valuable. A slave could be bought or sold like any other thing of value. A slave could be housed cheaply, fed cheaply and they also would produce other slaves. just like any other thing the farmer owned. Growing crops like cotton produced money for the owner. The south was still a farming or agricultural society. The north had become industrialized. The need for the south to produce more and more cotton increased their need for slaves. So the south didn't want to change. This resistance to change still occurs and has occurred many times in the past.