"WTF were they thinking?"
The point is that none of the crew knew enough to even know what they should have been thinking. They were all extremely inexperienced. They were looking for an adventure. They were told that this was going to be great fun, and that they were going out with a careful, competent, and highly experienced captain.
You really cannot blame the crew, in this case.
In fact, it reminds me a bit of the folks we have on this board pretty regularly, who post things like "I have no sailing experience, but I just bought a MacGregor 26, and I'm planning to sail around the world in it. What sort of radio do I need to take?"
And then, when someone tries to politely point out to them that they are completely unprepared for such an undertaking, and that their boat is wholly unsuited to a circumnavigation anyway, we get all the "Quit being such a naysayer! Let them live their dream!" postings in response. There are some people who need to hear a loud and hearty "NAY!" and who need to have their dreams at least deflated a little bit, if not burst completely.
Too bad that no one took aside the inexperienced crew members of the Bounty and gave them a realistic explanation of the risks involved, and the things they should be aware of, before they headed out. Clearly this was a case where yet another mutiny on the Bounty would have been the right thing.