Its more like this... do you piss off a star like Hugo Weaving as a studio , and force him to do a sequel he doesn't want no part of ? Because the fact is there could be another property down the line you need him to be in and your studio will have. By pissing the guy off and saying YOU MUST DO THIS....you won't get the guy later on. Its a you scratch my back and I'll scratch yours business.It's also possible that they could take him to court. Is it likely? Who knows? But the notion that people can just walk away from legally binding contracts without any expectation of consequences is just wishful thinking. The country ain't that free.
Plus what studio is gonna spend and waste money to get someone to do a film ? It sends bad PR for one thing . That they had to force a guy back to star in a film. To me it reminds me of why New Line settled with Snipes in his lawsuit. It was $5 million dollars...they could fart that much out in a day and write it off. So why waste $$$ fighting it.