Excellent. But People Seem To Be Missing The Point
Why didn't the customers try to escape, fight back, etc?
Because they didn't want to. They were bored of life. Tyler was the most severely affected by this staggering ennui, hence he was told up front that he would die. And he was fine with that.
The others clung to the notion of wanting to live but in truth... they simply didn't want to.
When the passion is gone, why continue? (I'm tempted to suggest that it's a metaphor for western civilisation as a whole but that might be a little pretentious).