Because studios and automakers have deep pockets and can weather a storm. Whereas workers and the actors not getting paid tom cruise money more or less can’t. Which is where donations to fund, helping out with food at the picket line, etc help. It stretches the union’s coffers a lot.
But also? Public backlash was a big factor for the last rounds of hollywood strikes. Some of it was people getting pissed off their shows weren’t on. But it was also acceptance of an environment where the scabs (sanctioned and unsanctioned) made off like gangsters.
As much as I love Conan’s work, a lot of his massive popularity boost was how he handled being contractually obligated to put on a show. I think he and Letterman handled it well (Leno was a disphit as always), but they definitely benefited.
But also? joss whedon and other creators who found “loopholes” similarly benefited. For crying out loud, a shitty, rather creepy, musical about fridging a girl on youtube was the most popular thing on the planet for a month or so.
And both of those eroded support within the union. Because, is it REALLY worth fighting a bit longer when someone else is getting set up for life by getting their scab on? And there were no negative repercussions.
Which is why SAG/WGA, through social media, went scorched earth on people like Stephen Amell and Drew Barrymore.
And this is true for all strikes. If your local starbucks is striking and everyone is getting pissed off they can’t get their coffee or angry that the sidewalk is blocked? That makes it clear to management that they can wait it out and will likely see a burst in customer traffic when it is over.