"Most of the people who work for corporations are fine, upstanding people, and are very interested in social issues."
---I agree with this. And yes, some corporations do donate significant amounts of their revenue to great causes (too bad donations amount a drop in the bucket though).
The problem is that the power of a public corperation lies with the shareholders, the executives, and the consumers. We all know that consumers in the USA, for the most part, want the cheapest possible goods (this is why so many shop at Walmart). In addition, most shareholders view profit as their number 1 objective, as do many executives. This profit sometimes becomes a conflict of interest as far as "doing the right thing" is concerned.
An example: You might be familiar with Bell's Brewing which makes some of the best microbrews in the world. Last summer there were rumors that Budweiser was attempting to buy Bell's. Lo-and-behold, Larry Bell is now being sued by Bell's Inc's shareholders for not disclosing a buy-out offer.
If Bud bought Bell's out, a seriously great part of Michigander brewing history would be smeared. There would be many upset beer drinkers saying Larry Bell "sold out," and rightly so. Did Larry do the right thing or are the money-grubbing shareholders right (they would have sold in a second, trust me)? You could argue either way, but IMO I'm with Larry.
That was a fairly lighthearted example but lets get serious now. Many publicly owned corporations do whatever it takes, within legal limits (and sometimes not), to make the largest profit. Thats why companies outsource to areas that produce goods cheaply. Is it good to exploit cheap labor or rape poor countries of their resources? No, it is not good, it's terrible (ie: evil).
Good publicly traded companies are mainly the result of consumers and shareholders who are educated and give-a-damnn. Too bad those people are in the minority in the USA. Are corporations evil? IMO, consumer ignorance is the biggest problem, but yes, cooperations are ruining this country (and many others) with their capitalist-extremism.
Cheers to Larry Bell!