It's really fucking common in the internet wild. It's even common offline.
"Just pack up your entire life and move out of here if you don't like it here. No one is holding a gun to your head to stay." 
Oh, I did, but it took years of planning, preparation, savings, and an early retirement with the penalties that entailed. There was no gun, but I couldn't whisk myself out of Bazinga Land in CA any faster than I could sell a flooded house to Aquaman.
That's it. That's the post. No one held a gun to my head to post this, but I did it anyway.
I think they talk like this to themselves. Every time they realize how awful life is they silence their own critique with "gun to your head" discourse to dismiss their suffering as a self-created illusion.
I think you may be right; it's a sunk-cost fallacy expanded over a lifetime where it'd be too painful to admit they were slowly fucked over by the system they supported.