Businesses who act unethically often do so because of the "moral minimum", which means that:

The company only needs to provide maximum value for its shareholders, and the environment does not help a company maximize value

The company conducted a cost-benefit analysis and determined that it would be cheaper to disobey the law than to follow it

The law does not take morals or intent into consideration, and only deals with the facts facing businesses today

The law sets forth a minimum set of requirements for companies to abide by, so unethical behavior is not necessarily illegal