Goofs

Suzie is killed when one of the robots blows up a gasoline can in her hand with a laser. Yet, when we see Suzie's burning body, the gasoline can is still intact.

When the robot blows up the gas can in Suzie's hand, the only thing that burns is Suzie's body. The explosion should have sent burning fuel all over the place.

When Alison hangs over the railing to escape the robot, the rail that she hangs by changes frequently, even though she doesn't climb up or down.

After leaving the gun store, Tony O'Dell is carrying a revolver in his right hand and a propane tank in his left. When asked if he knows how to use the pistol, he replies (in closeup) that he's seen "Dirty Harry" and holds up the pistol with both hands on the grip. Next shot he's carrying the propane tank again.

Technician's donut is eaten after the lightning strikes.

Gasoline cans in stores are always empty. There was no place for the girls to get gas to fill them.

Unless incendiary ammunition is used, bullets puncture propane tanks but do not cause them to explode.

The gasoline can that Allison shoves towards the robot spreads a pool of burning gasoline, but nothing caused the can to rupture. To be effective, gasoline bombs need to be made from something breakable.

When Alison is getting attacked in the pet store by one of the killbots, several tarantulas and even a snake crawl on her as she hides under a shelf, all clearly live animals. Once the killbot leaves and she emerges from her hiding place, it is clear the spiders placed on her are just plastic toys as they fall off with no movement of their own and are much smaller than the live tarantulas.

New paint cans are always filled to the top. When Allison opens paint cans they are nowhere near the top.

In the fight with the last killbot, Ferdy shoots eight shots from a six shot revolver.

Obvious fake spiders when Allison gets out of her cover in pet store.

Throughout the entire movie, people can be seen walking around in the background on different floors of the mall, even though it's supposed to be closed.

A robot's laser blows Leslie's head to bits, later the lasers' only minorly wound two of the main characters (with such small wounds).

There's no explanation for how or why the Killbots disposed of the first technician and removed all blood and other evidence of what had occurred. They may move like Roombas, but they weren't designed or equipped for cleanup tasks.