The Signs school of Chekhov’s gun. Water. More water. Water everywhere! Oh no! Aliens! I wonder what their weakness is 😉
"What's this? I said, take only what you need to survive."
"My industrial-strength hair dryer. And I can't live without it!!"
In the event of an apocalypse and you do happen to pack a great bag of actual essentials .... someone bigger stronger and with a gun is going to murder you for it.