People don't listen to that preflight announcement stuff because they've heard it a hundred times before.
Right. What has the attendants so mad is that people are now being obvious about it.
People who've flown even a couple of times before don't need to listen... I know how to wear a seatbelt and that my seat cushion can be used as a floatation device..."
.. the only problem being that, if you're in a plane with actual life-vests under the seat, the seat cushions might not be easily detachable as they're not the primary flotation device. Also, is your life-vest located under your seat or in the bin above you? If it's under your seat, can you *reach* it? More-importantly, which of the exit doors are the kind that swing in and stay there? Which ones come completely off and need to be tossed out the doorway? Do you pull the door into the cabin from the top or bottom? Which doors release by swinging a single arm? Do you swing it up or down? Which ones don't have an arm, but a pull-down lever? Which of those have an additional cover over the lever which you must pull down *first*? Which doors should you not open in a water landing? Which doors have escape-slides? Which ones auto-deploy when you remove the door? Which ones require a tab to be pulled? Which ones detach to become rafts? How do you detach them?
There *are* differences, and the time to figure out what there is not when you've got 2-3 seconds before a mass of onrushing, panicking humanity presses you up against the door. That's why I try to always "review the passenger information booklet located in [my] seat pouch". Even if I'm not on an exit row, I make sure that I know how to open the nearest door, because the dudes *in* the exit row might be thinking "Hey, I know how to operated a damn seatbelt..."