First off, those who aren't PROFESSIONAL PILOTS should keep their insane theories to a minimum. I myself am a retired pilot who flew with a major airline for 32 years.
But look, airlines these days... some days I'd walk out the cockpit and it looked like a prison riot had taken place. I'm talking cups everywhere, graffiti, and seat-backs which had been slashed with knives somehow. Ridiculous. Trying to get a cup of coffee without lipstick on the rim of the cup was impossible, and that was when the stewardesses weren't busy cooking whatever it is they thought they were cooking. And I can't count the number of times I had to go back and settle some beef between a flight crew member and a passenger, lest we have someone trying to open an emergency exit at 30,000 ft.
Point being it's obvious that something happened with the pilots, but lets not libel them by delving into their psychology without taking all of this into account. The the poor guys up front just might not have been able to stand the smell of the plane, and theres only so many times you can take being told that the lady in 23F wants a pillow while you're navigating mountains in a fog.