Obviously, some of the most voracious supporters of the oft-maligned protection acts working their way through the houses of government are members of the entertainment industry. You may know at least two of these associations better by their choice of acronyms: The MPAA and the RIAA. Clearly, these to entities have the most to lose in a non-SOPA protected world, at least if let spokespersons from each group tell it.
While the protectors of the intellectual property that's being produced may support SOPA in all of its forms, in this case, the MPAA (Motion Picture Association of America), it appears as if the working class members of Hollywood aren't as supportive of the bills as the ruling class is. As pointed out by TechDirt, there exists a petition that is being supported by various Hollywood union members. However, these aren't necessarily actors and actresses. Instead, the majority of the Hollywood SOPA dissent is coming from behind-the-scenes employees; the camera operators and studio grips, for example.
The stance of the signees is along the same lines as the rest of those who oppose SOPA. From the petition letter:
Firstly, they won't solve the "Piracy Problem". These bills overstep their boundaries in regards to free speech and seem to be remarkably ineffective in actually stopping piracy from happening. Although SOPA makes it possible to block domain names that infringe on copyrights in some way, it doesn't block numeric IP addresses, so you could still access the offending site if you knew the IP address...
Secondly, the potential for government control and censorship is extremely high. One of the biggest issues with both PIPA and SOPA is the broad language used in the bills to define piracy. SOPA, for example, would broaden the definition of copyright infringement to an extreme.
The petition page also has a comment section, allowing signees to state why they support the anti-SOPA petition. This is where you find that not everyone who works in Hollywood supports the current anti-piracy bills, much to the surprise of the associations that would say otherwise:
Proud member of IATSE Local One and horrified that my union is supporting this.
I'm a member and officer of IATSE Local 839 (The Animation Guild). I am in favor of protecting intellectual property rights, but I am opposed to SOPA/PIPA.
One more for good measure:
I'm a proud Local One and USA829 member, and am appalled to find my union supporting this act. While I agree that piracy is bad, this act is ill-designed by legislators with no clue how the internet works, and guided by greedy corporations who have ulterior motives, and who have a track record of abusing the DMCA the same way they'll abuse this.
It will do nothing to stop it, will give unfettered power prone to abuse to corporations who don't deserve it, will short circuit due process, and will have huge unintended negative effects on the internet as a whole.
So while the powers that rule Hollywood/the entertainment industry are on board with any bill that tries to prevent piracy, no matter how potentially damaging it is to the structure of the Internet, those work the hands-on jobs for the movie industry aren't blindly following SOPA/PIPA. They recognize the potential damage piracy can have, but they aren't about to get onboard with something that could damage the structural integrity of the Internet.