I got in trouble for pointing this out once years ago.

  Jurassic Park.

  It had just come out on HBO. Had to be '95 or so and before I
  ever saw any "movie rules" lists.

  I'm watching it with my sister and her boyfriend.

  They're walking towards a dangerous situation, early on in the
  movie. There's a black guy among whites. Not much personality
  beyond stereotypical "you'll forget me after this scene".

  I said, "He's gonna die first. He's black. It's going to be
  gruesome and they'll show a body part of his detached".

  They had a fit! Called me racist and all sorts of things and
  almost kicked me out of the room. I said, "I'm not racist;
  that's just what they do in movies!"

  Anyway, I think his arm got chewed off or leg or something a few
  minutes later.

  They didn't speak to me for the rest of the film, but as a
  parting "I told you so" from me, I said, "It's because
  movie-goers are less picky about mistakes in african american
  skin tone on the props, but very particular about caucasian skin
  tone mistakes."

  Last time they invited me to watch a movie with them too.