Other pressure is exerted by corporate employees who are more aware of and concerned about environmental issues. Overall, where a corporation does misbehave, this is becoming ever more visible. Take the public outcry over claims relating to the behaviour of companies such as Nestl in its marketing of baby milk in the Third World or Nike and production in Third World sweatshops. Such behaviour can make national and international news and this is much more powerful than advertising - it can make or break a company in terms of image. The Internet too is a powerful information tool here.
Secrecy is almost impossible today.
My conclusion is that improper behaviour is probably decreasing steadily, prompted not only by a fear of poor publicity, but by an increasing ethical consciousness. There can also be hefty financial penalties for ethical or environmental misdemeanours. Meanwhile, responsible behaviour can be rewarded by official and public recognition which is good for the corporate image, recruitment and business ratings. Ultimately I would say that it may be possible for companies to do well by doing good. The subject of my PhD dissertation some thirty-five years ago was American marketing in the European Common Market.