Revealing mistake: When Hank severs the head of the second zombie with the shears, the body staggers against the barricade, and one of the planks that is supposedly keeping away a throng of zombies from the HW store wobbles going noticeably out of place. (01:05:50)
Revealing mistake: When the zombie crawls into the hardware store breaking through the bottom part of the barricade, you can already see on the wood plank the line where the wood is supposed to snap in half. (01:05:20)
Answer: It was in the script that they would die. Ronnie stated he knew it would end badly because the director gave him the full script ahead of time.
Invader_Gir