Too many of us watch movies as if we were proofreading them. Not only does this lead to ridiculous--and fruitless--conversations about everything from what a decapitation really looks like to how it really looks when a train explodes, it also robs us of enjoyment. Especially when this is the main focus.
This is even more ridiculous with the horror or sci-fi crowd. Countless times I've been watching a movie about ghosts, a vampire, a zombie apocalypse, or some other such nonsense, only to have some Poindexter throw a fit about some pedantic detail like an unrealistic gunshot wound. Now granted, that may not be what it would really look like if someone suffered a shotgun blast to the face, but come on; you're watching a movie about the dead coming to life. Realism is relative.