In nature, shiny animals are covered in poison slime, or scales, or a carapace. All of which are gross and can kill us.
Minerals that are shiny are valuable, and somebody will kill us for them. Or they are wet, and therefore slippery, meaning we'll slip on them and die.
Mirrors are shiny. Serial killers and evil ghosts always appear behind us in the mirror before killing us.
Shiny cars are always driven by self-obsessed douchebags who usually are talking on shiny cell phones when they run over us. Which kills us.
Bullets are shiny. Swords are shiny. Both kill. A shiny letter opener can also kill with a little work.
Greeting cards, kittens and ice cream cones are not shiny. Trees are not shiny. Nobody ever dies from a tree unless a) it blows over during a storm, in which case the rain makes the tree wet and therefore shiny and b) it falls on someone who cuts it down with a chainsaw. Which is shiny.
The scariest movie of all time is The Shining. COINCIDENCE?