Continuity mistake: Just before Steve Hadley is killed by the Merman, his tie is wrapped around his neck. When the Merman attacks him, his tie is worn properly. (01:19:40)
The Cabin in the Woods (2012)
Trailers
Directed by: Drew Goddard
Starring: Chris Hemsworth, Anna Hutchison, Kristen Connolly, Fran Kranz
More trailers
More mistakes in The Cabin in the Woods
The Director: This is all most unpleasant. I know you can hear me. I hope you'll listen. You won't get out of this complex alive. What I want you to try to understand is that you mustn't. Your deaths will avert countless others. You've seen horrible things: an army of nightmare creatures. And they are real. But they are nothing compared to what lies beneath us. There is a greater good, and for that you must be sacrificed. Forgive us... And let us end it quickly.
Trivia: Actual "Cannabis Experts" were brought in to consult with actor Fran Kranz, so he could properly portray a convincing stoner in the film.
Question: Is there a reason, that a facility full of monsters would ever, under any circumstances have a System Purge button? Is it just to make satire of the fact that the antagonist is usually stupid?
Answer: As you said, it is a satire of the common Deus Ex Machina trope you find in such films.