When I watch a movie for the very first time, I like to pay attention. I like to take in the images on the screen. I like to let my brain go to town analyzing the characters and the plot and the dialogue. It's not as if I pull every film I see apart and attempt to determine what the creators were trying to say with their use of symbolism. I know that sort of thing is out there, but I generally just watch a movie intending to be entertained.
That doesn't mean I don't pay attention when I've seen a movie dozens of times though. But with those kinds of movies, the ones I can watch over and over again, something becomes more fun about them. I won't talk during one of those first-timers, but when I'm watching something like Back to the Future, talking becomes a part of the viewing experience.
When I've seen a movie more than a few times, it becomes incredibly easy to tear it apart. When watching a plot unfold for the hundredth time, it's easy to find the holes and exploit them through biting sarcasm. There's something fun about mocking beloved movies.
But don't worry. I would never do that to Back to the Future, the most awesome movie ever made. Ever.