Let's apply the same logic to people then. "John scammed his neighbour of his life savings, we don't need to lock him up because lots of people will refuse to associate with him or supply him with goods and services."

Making loss of business or minor fines the only mechanism for correcting behaviour, means that the leaders can view antisocial and unethical behaviour as a cost benefit tradeoff. And the lack of personal accountability means the company leadership has very limited downside, even if they completely screw up.