You clearly misunderstood what "if companies can freely poison everyone, profits go up" meant. It's not that the rich are poisoning people for its own sake and laughing manically to themselves. It's that removing regulations and lowering safety standards allows companies to recoup the money they were legally required to spend on upholding them, hence increasing their profits at the cost of public health. Which, I hope you'll concede, is a morally terrible thing to do.