So you think it's unreasonable for an employer to be unhappy with a large group of people taking an extra 90 minute "lunch" with no reprisal?
Say, you fired some ***** who's been with you a long time. But he gets the job done, and everyone on the floor likes him. But he's a pain in the arse, hard to deal with, and has an attitude problem with owners/management. And you've been looking for a good reason to fire him. HA! Got him, he's been skimming on the time cards. Good enough, time to go!
Now that he's gone, everyone on the floor is mad about it... they decide collectively to do nothing for almost 2 hours. No printing, no machines running, trimming, laminating... got customers up in the lobby waiting for their prints or whatever. They don't give a crap about whatever little power struggle is going on in the back. They just want their signs. They start demanding their money back, walking out the door and down the street to your competitor. All the while with a story to tell about your little coup de gras that's going on.
What do you do? You squash the insurrection. That's what you do. If they really valued their jobs, and their family's wellbeing, then they'd have kept on doing what they are paid to do. It's not slavery.