Earlier quoted context omitted.
That's not really fair. The people who run corporations have a fiduciary responsibility. (There are of course caveats, and we can argue all day over whether or not SOPA is unconstitutional or otherwise illegal, but you get the point.) If you are a movie studio, SOPA is a great idea for your bottom line. I don't think it's fair to call everyone who is in favor of SOPA either evil or stupid, even if SOPA itself is both…
You appear to be suggesting a variation on the Nuremberg defense. "Your honor, I'm not evil! I was just following orders... errr.. I mean I had a responsibility to my shareholders!" I'm sorry, I simply cannot take your line of reasoning seriously.
That usually happens when you invoke Godwin.
How about you put it this way - we'll use the RIAA as an example, but lots of companies support SOPA for many reasons: A bunch of CEOs employ thousands (tens of thousands?) of people and see that their primary modern-day asset - copyrighted music - is in grave jeopardy. They know that modern technology makes this asset increasingly hard to control, and that unlike in the vinyl, 8-track, cassette, and early CD eras, they can longer create artificial scarcity as they once did.
They know that if that threat continues to grow as it does, they can't provide distribution as an asset to artists, which used to be a big reason you signed with a major label. That means they have to scale their operations back in a big way, which means letting a lot of people go and less profit (CDs sales actually are still a profitable business). Since they firmly believe in the protections copyright affords, and they've worked in this industry a long time, they see the better approach to be attacking the copyright infringement. And their job is to keep their company running the best they can. Now is it so surprising they consider the second option?
They may or may not understand that SOPA endangers many aspects of how the internet works. But they aren't necessarily acting in bad faith just because they support SOPA.
I know the niche hacker news fills is particularly well-targeted by SOPA, and that can lead to a circlejerk like any other online community with common beliefs, but it's harmful to discourse to assume those who you disagree with you on SOPA are inherently evil as a result. That's why Godwin is such a joke - it's almost never an appropriate analogy to compare your opponents in a {political,religious,technology,etc} debate to those who participate in genocide.